System and method for glucose monitoring

ABSTRACT

A glucose biosensor includes a plurality of optical fibers configured for placement within the ear canal. A first optical fiber emits light into the ear canal. A plurality of other optical fibers capture and transmit the reflected light back to the glucose biosensor. A plurality of photodetectors are configured in the glucose biosensor to detect the reflected light from the plurality of optical fibers. The glucose biosensor processes the detected light from each photodetector to determine a glucose level measurement. In an embodiment, the glucose biosensor also obtains a second glucose level measurement using another method and determines a calibration for the first glucose level measurement using the second glucose level measurement.

CROSS REFERENCE TO RELATED APPLICATIONS

The present application claims priority under 35 U.S.C. § 120 to U.S.patent application Ser. No. 14/866,500 entitled, “System and Method forGlucose Monitoring,” filed Sep. 15, 2015, and hereby expresslyincorporated by reference herein, which claims priority under 35 U.S.C.§ 119 to U.S. Provisional Application No. 62/194,264 entitled, “Systemand Method for Glucose Monitoring,” filed Jul. 19, 2015, and herebyexpressly incorporated by reference herein.

FIELD

This application relates to systems and methods of non-invasive bloodanalytic monitoring, including a glucose biosensor that detects glucoselevels using one or more techniques. More particularly, the glucosebiosensor transmits light into an ear canal and processes the lightreflected from the ear canal to determine blood analytics, such as aglucose level, and wirelessly transmits the blood analytics to a gatewayor glucose meter or user device.

BACKGROUND

Various techniques are available for obtaining blood glucose levels inpatients with diabetes. One technique requires a small blood sample fromthe patients, e.g. from a finger prick. The blood sample is placed on achemically prepared test strip and inserted into a glucose meter thatanalyzes the test strip and provides a blood glucose level.Unfortunately, to monitor their blood glucose levels, diabetics may needto prick their fingers multiple times within a day. This monitoringprocess can be painful, inconvenient and creates possible exposure toinfections. Additionally, measurements with these devices present anerror of uncertainty range between 6-7% depending on sample quality,human error, calibration, humidity, and hygiene in the sample area.

Thus, there is a need for an accurate, non-invasive blood analytic andglucose monitoring method and device that eliminates the pain of drawingblood as well as eliminates a source of potential infection.

SUMMARY

According to a first aspect, a biosensor includes a light emitter anddetector circuit configured to emit light at a first wavelength and asecond wavelength onto tissue of a user and obtain a first spectralresponse of reflected light at the first wavelength and a secondspectral response of reflected light at the second wavelength. Thebiosensor also includes a processing circuit configured to obtain afirst glucose level measurement using the first spectral response andthe second spectral response; obtain a second glucose level measurementusing another measurement technique, wherein the another measurementtechnique includes at least one of: Near-Infrared Spectrometry, RamanSpectrometry, Thermal Emission Spectrometry, flourophoresence,photoacoustic spectrometry, or another glucose measurement method; anddetermine a calibration for the first glucose level measurement usingthe second glucose level measurement.

According to a second aspect, a biosensor comprises a light emitter anddetector circuit configured to emit light in an IR and visible spectrumonto tissue of a user and obtain a first spectral response includingreflected IR light and a second spectral response including reflectedvisible light. The biosensor also includes a processing circuitconfigured to obtain a first glucose level measurement using a ratiodetermined from the first spectral response of the reflected IR lightand the second spectral response of the reflected visible light; obtaina second glucose level measurement using another measurement technique,wherein the another measurement technique includes at least one of:Near-Infrared Spectrometry, Raman Spectrometry, Thermal EmissionSpectrometry, flourophoresence, or photoacoustic spectrometry; anddetermine a calibration for the first glucose level measurement usingthe second glucose level measurement.

According to a third aspect, a biosensor includes a light emitter anddetector circuit configured to emit light at a first wavelength and asecond wavelength onto tissue of a user and obtain a first spectralresponse of reflected light at the first wavelength and a secondspectral response of reflected light at the second wavelength. Thebiosensor also includes a processing circuit configured to obtain afirst glucose level measurement using the first spectral response andthe second spectral response; obtain a second glucose level measurementusing a blood test; and determine a calibration for the first glucoselevel measurement using the second glucose level measurement.

In one or more of the above aspects, the first wavelength is in aninfra-red (IR) spectrum and the second wavelength of light is in avisible spectrum; and wherein the processing circuit is furtherconfigured to obtain the first glucose level measurement using a ratioof the first spectral response and the second spectral response. Theratio of the first spectral response and the second spectral responseare calculated based on Beer-Lambert law.

In one or more of the above aspects, the processing circuit is furtherconfigured to: obtain the second glucose level measurement from userinput, wherein the second glucose level measurement includes a bloodtesting method.

In one or more of the above aspects, the biosensor further comprises awireless transceiver configured to communicate with a user device,wherein the wireless transceiver receives the second glucose levelmeasurement from the user device.

In one or more of the above aspects, the processing circuit is furtherconfigured to determine a difference between the first glucose levelmeasurement and the second glucose level measurement and adjust thefirst glucose level measurement using the difference.

In one or more of the above aspects, the processing circuit is furtherconfigured to analyze one or more other spectral responses to determinethe second glucose level measurement, wherein the second glucose levelmeasurement is obtained using at least one of: Near-InfraredSpectrometry, Raman Spectrometry, Thermal Emission Spectrometry,flourophoresence, or photoacoustic spectrometry.

In one or more of the above aspects, the processing circuit is furtherconfigured to obtain the second glucose level measurement from userinput, wherein the second glucose level measurement is obtained using atleast one of: Near-Infrared Spectrometry, Raman Spectrometry, ThermalEmission Spectrometry, flourophoresence, or photoacoustic spectrometry.

In one or more of the above aspects, the processing circuit is furtherconfigured to determine an average or mean of the first glucose levelmeasurement and the second glucose level measurement; determine adifference between the first glucose level measurement and the averageor mean; and adjust the first glucose level measurement using thedifference.

In one or more of the above aspects, the light emitter and detectorcircuit is configured to detect a frequency shift in reflected lightfrom a predetermined frequency range of emitted light and the processingcircuit is further configured to obtain the second glucose levelmeasurement using Raman Spectrometry.

In one or more of the above aspects, the processing circuit is furtherconfigured to obtain the second glucose level measurement by measuringan amount of infrared radiation naturally emitted from tympanic membranein an ear canal using Thermal Emission Spectrometry.

In one or more of the above aspects, the light emitter and detectorcircuit is configured to emit light in a 430 nm range onto tissue of theuser and determine a power or energy level of fluorescent emission inthe 430 nm range. The processing circuit is further configured tocorrelate the power or energy level of fluorescent emission to obtainthe second glucose level measurement.

In one or more of the above aspects, the light emitter and detectorcircuit is configured to obtain resonance absorption peaks in a near-IRspectrum reflected from tissue of the user; and wherein the processingcircuit is further configured to compare the obtained resonanceabsorption peaks to expected resonance absorption peaks for glucose todetermine the second glucose level measurement.

In one or more of the above aspects, the processing circuit is furtherconfigured to determine an average or mean of the first glucose levelmeasurement and the second glucose level measurement; determine adifference between the first glucose level measurement and the averageor mean; and adjust the first glucose level measurement using thedifference.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 illustrates a schematic drawing of an exemplary embodiment of aglucose biosensor.

FIG. 2 illustrates a schematic drawing of another exemplary embodimentof a glucose biosensor.

FIG. 3 illustrates a schematic drawing of another exemplary embodimentof a glucose biosensor.

FIG. 4 illustrates a schematic drawing of another exemplary embodimentof a glucose biosensor.

FIG. 5 illustrates a schematic drawing of an exemplary embodiment of acasing of a glucose biosensor.

FIG. 6 illustrates is schematic drawing of another exemplary embodimentof a glucose biosensor.

FIG. 7 illustrates a logical flow diagram of an exemplary method fordetermining a glucose level measurement.

FIG. 8 illustrates a logical flow diagram of an exemplary method forglucose monitoring in more detail.

FIG. 9 illustrates a logical flow diagram of an exemplary method forobtaining a glucose level measurement.

FIG. 10 illustrates a logical flow diagram of an embodiment of anexemplary method for calibrating the glucose biosensor.

FIG. 11 illustrates a schematic drawing of an exemplary embodiment of agateway.

FIG. 12 illustrates a schematic block diagram of another exemplaryembodiment of a gateway.

FIG. 13 illustrates a schematic block diagram of an exemplary embodimentof a glucose meter.

FIG. 14 illustrates a schematic block diagram of an exemplary embodimentof an exemplary communication network in which the devices describedherein may operate.

FIG. 15 illustrates a schematic block diagram of an exemplary embodimentof a user device.

FIG. 16 illustrates a schematic block diagram of an exemplary embodimentof a graphical user interface.

FIG. 17 illustrates a schematic block diagram of an exemplary embodimentof another graphical user interface.

FIG. 18 illustrates a schematic block diagram of an exemplary embodimentof another graphical user interface.

FIG. 19 illustrates a schematic block diagram of an exemplary embodimentof another graphical user interface.

FIG. 20 illustrates a schematic block diagram of an exemplary embodimentof an analytic biosensor.

FIG. 21 illustrates a logical flow diagram of an exemplary method forobtaining a glucose level measurement using a plurality of measurementtechniques.

FIG. 22 illustrates a logical flow diagram of an exemplary method forusing a combination of measurement techniques to enable autocalibration.

FIG. 23 illustrates a schematic block diagram of an exemplary embodimentof an IR spectroscopy biosensor.

FIG. 24A illustrates a logical flow diagram of an embodiment of a methodfor glucose monitoring using IR absorption spectroscopy.

FIG. 24B illustrates a graph of absorbance change versus wavelength forglucose and water.

FIG. 25 illustrates a schematic block diagram of an embodiment of a skinbiosensor.

FIG. 26 illustrates a schematic block diagram of an embodiment of a skinpatch including a skin biosensor.

FIG. 27 illustrates a schematic block diagram of an embodiment of afinger clip including the skin biosensor.

FIG. 28 illustrates a logical flow diagram of an embodiment of anothermethod for glucose monitoring using IR absorption spectroscopy.

DETAILED DESCRIPTION

The word “exemplary” or “embodiment” is used herein to mean “serving asan example, instance, or illustration.” Any implementation or aspectdescribed herein as “exemplary” or as an “embodiment” is not necessarilyto be construed as preferred or advantageous over other aspects of thedisclosure. Likewise, the term “aspects” does not require that allaspects of the disclosure include the discussed feature, advantage, ormode of operation.

Embodiments will now be described in detail with reference to theaccompanying drawings. In the following description, numerous specificdetails are set forth in order to provide a thorough understanding ofthe aspects described herein. It will be apparent, however, to oneskilled in the art, that these and other aspects may be practicedwithout some or all of these specific details. In addition, well knownsteps in a method of a process may be omitted from flow diagramspresented herein in order not to obscure the aspects of the disclosure.Similarly, well known components in a device may be omitted from figuresand descriptions thereof presented herein in order not to obscure theaspects of the disclosure.

Overview

In first exemplary embodiments, a glucose biosensor includes opticalfibers to emit ultraviolet (UV) light into an ear canal of a patientwhile one or more photodetectors in the glucose biosensor detect thereflected UV light. The glucose biosensor processes the reflected UVlight from the ear canal to determine a glucose level measurement. In anembodiment, the glucose biosensor includes at least three optical fibersconfigured for placement within the ear canal. A first optical fiberemits UV light into the ear canal while the two other optical fiberscapture and transmit the reflected UV light back to the glucosebiosensor. Two photodetectors are configured in the glucose biosensor todetect the reflected light from the two optical fibers. The glucosebiosensor processes the detected light from each photodetector todetermine a glucose level measurement. In an embodiment, the glucosebiosensor also includes a wireless interface to transmit the glucoselevel measurements to a glucose meter and/or a gateway. The gatewayincludes a communications interface for communicating over a wired orwireless network and may transmit the glucose level measurements to ahospital, doctor, or pharmacy or other third party caregiver. Thegateway may also communicate the glucose level measurements to a centralapplication server that includes a web-based user application fortracking and monitoring glucose level measurements and other biosensordata.

In second exemplary embodiments, an analytic biosensor is configured toperform monitoring of biometric analytical markers, including glucoselevels, using a combination of two or more non-invasive techniques thatanalyze light reflected from an ear canal. For example, the techniquesmay include: near infrared spectroscopy, Raman spectroscopy,flourophoresence, thermal emissions, photoacoustic and polarimetry. Inuse, two or more of the techniques are employed to obtain biometricmeasurements. An average or mean of the biometric measurements from thetwo or more techniques is used for calibration of the analyticbiosensor. The analytic biosensor is also configured to non-invasivelymeasure other biometric data, such as pulse rate, blood pressure,peripheral oxygen (SpO2) saturation amounts, body temperature, variouselectrolytes and many common blood analytic levels, such as bilirubinamount.

Exemplary Embodiments of a Glucose Biosensor

FIG. 1 illustrates a schematic drawing of an exemplary embodiment of aglucose biosensor 100. The glucose biosensor 100 includes a processingcircuit 120, a memory 122 and a wireless transceiver 126. For example,the memory 122 is a non-transitory, processor readable medium thatstores instructions which when executed by the processing circuit 120,causes the processing circuit 120 to perform one or more functionsdescribed herein. The wireless transceiver 126 may operate in the 900MHz range over a serial link using a proprietary protocol or may utilizea standard protocol in the 900 MHz range, such as IEEE 802.11ah, Zigbee,IEEE 802.15-11 etc. In other embodiments, the wireless transceiver 126operates in one or more other wireless frequency bands or protocols,such as near field communication, short range radio frequency, RFID,infrared link, Bluetooth, or other short range wireless communicationprotocol.

The glucose biosensor 100 also includes a light emitter and detectorcircuit 102 having a first photodetector circuit 104, a secondphotodetector circuit 106 and a light source circuit 108. The lightsource circuit 108 includes one or more light sources 128, such as alight emitting diode (LED) or a laser circuit and a driver circuit 140for controlling the one or more light sources 128. The firstphotodetector circuit 104 and the second photodetector circuit 106 eachinclude, for example, a photodiode or other component operable to detectUV light and convert the detected UV light to an analog signal. Thefirst photodetector circuit 104 is coupled to a first analog to digitalA/D circuit 116, and the second photodetector circuit 106 is coupled toa second A/D circuit 118. In an embodiment, UV light is in a range fromapproximately 300 nm to 10 nm, including near UV light in a range fromapproximately 300-400 nm.

The light emitter and detector circuit 102 is optically coupled to aplurality of optical fibers 110, 112, 114. In an embodiment, theplurality of optical fibers 110, 112, 114 includes a first optical fiber110 optically coupled to the light source circuit 108, a second opticalfiber 112 optically coupled to the first photodetector circuit 104 and athird optical fiber 114 optically coupled to the second photodetectorcircuit 106. The plurality of optical fibers 110, 112, 114 are encasedwithin an earpiece or ear bud or other casing that is configured to fitwithin an outer ear canal of a patient. In an embodiment, a firstoptical fiber 112 and a second optical fiber 114 are optically coupledto the first and second photodetector circuits 104 and 106,respectively. The first and second optical fibers 112, 114 arepositioned around a third optical fiber 110 that is optically coupled tothe light source circuit 108. As such, the optical fiber 110 opticallycoupled to the light source circuit 108 is configured to rest within themiddle of the other two outer optical fibers 112 and 114. However, otherconfigurations and numbers of the plurality of optical fibers 110, 112,114 may also be implemented.

In use, the light source circuit 108 emits a series of pulses of lightin one or more intervals, e.g. three pulses of light in each of at leastthree intervals. For example, in a first interval, such as a 10 msinterval, the light source circuit 108 emits at least three pulses oflight. In a second interval, the light source circuit 108 emits threepulses again and three more pulses in a third interval. The light sourcecircuit 108 then waits for a predetermined waiting period, such as 30-60seconds, before emitting another series of pulses in one or moreintervals. The waiting period between the series of pulses helps toprevent a rise in ear canal temperature that may affect the results.This process of emitting a series of pulses in one or more intervals andthen waiting for a predetermined waiting period is continuously repeatedor may be repeated at predetermined time periods, such as at 5 minute,15 minute or longer time periods.

The emitted light 130 is transmitted into the outer ear canal by themiddle optical fiber 110. The emitted light 130 is reflected back bymembranes in the outer ear canal and/or the inner ear canal. The outeroptical fibers 112 and 114 capture the reflected light 132 and transmitthe reflected light 132 to the first and second photodetector circuits104, 106, respectively. The first photodetector circuit 104 detects thereflected light 132 and generates a first detected light signal 134 a.The first detected light signal 134 a is transmitted to a first A/Dcircuit 116 configured to convert the first detected light signal 134 ainto a first digital signal 136 a. Similarly, the second photodetectorcircuit 106 detects the reflected light 132 and generates a seconddetected light signal 134 b. The second detected light signal 134 b istransmitted to a second A/D circuit 118 that is configured to convertthe second detected light signal 134 b into a second digital signal 136b. The processing circuit 120 receives and processes the first andsecond digital signals 136 a, 136 b to determine a glucose levelmeasurement.

In an embodiment, the light source circuit 108 emits light in the UVrange, e.g. at approximately 430 nm. Blood based proteins associatedwith glucose levels in the blood stream reflect UV light at lower energylevels. Thus, the reflected UV light detected by the glucose biosensor100 has a lower energy level than the emitted light. The decrease in theenergy level of the reflected UV light provides an indicator of bloodglucose levels. The glucose biosensor 100 in an embodiment determines areceived power level of the reflected UV light from the first and seconddigital signals 136 a, 136 b and performs an integral summation of thereceived power levels to determine a glucose level measurement, asdescribed in more detail herein.

In another embodiment, the glucose biosensor 100 performs a spectralanalysis of the reflected UV light to determine a glucose levelmeasurement. For example, the reflected UV light includes spectralinformation of the emitting body tissue. The spectral characteristics ofthe reflected UV light are analyzed by the glucose biosensor 100 todetermine a glucose level measurement.

In another embodiment, a phase change of the reflected UV light isdetected. The phase change of the reflected UV light between the firstphotodetector circuit 104 and the second photodetector circuit 106 canbe translated into a glucose level measurement.

In another embodiment, the glucose biosensor 100 transmits infrared (IR)light into the ear canal rather than near UV light, and the first andsecond photodetector circuits 104, 106 are operable to detect thereflected IR light. For example, in an embodiment, the light sourcecircuit 108 transmits IR light at approximately 940 nm. The glucosebiosensor 100 processes the reflected IR light to determine glucoselevel measurements. In another embodiment, the light source circuit 108is operable to transmit light in a plurality of spectrums. For example,one or more light sources 128 emit a combination of two or more of UVlight, visible light and IR light. The first and second photodetectorcircuits 104, 106 are operable to detect the light in the plurality ofspectrums. The glucose biosensor 100 processes the reflected light 132in the plurality of spectrums to determine a glucose level measurement.

In another embodiment, the glucose biosensor 100 performs a plurality oftypes of analysis to determine a glucose level measurement. For example,the glucose biosensor 100 may perform a combination of two or more of: apower level analysis, a spectrum analysis, a phase change analysis or atemperature analysis. The glucose biosensor 100 may then average orweight the glucose level measurements determined from each of theplurality of types of analysis to determine a final glucose levelmeasurement. When a difference between two or more of the glucose levelmeasurements are greater than a predetermined threshold (such as a 5%difference), the glucose biosensor 100 may determine that themeasurements are in error and perform the testing and analysis again.After repeated errors in the glucose level measurements, the glucosebiosensor 100 may request that alternate glucose monitoring methods areperformed, such as a finger prick method.

Though three optical fibers 110, 112, 114 are illustrated, the glucosebiosensor 100 may employ additional optical fibers. For example,additional optical fibers may be coupled to additional photodetectorcircuits to detect reflected light 132. Additional optical fibers mayalso be coupled to additional light source circuits 108 to emit lightinto the ear canal. For example, a first optical fiber coupled to afirst light source circuit 108 may emit light in a first spectrum and asecond optical fiber coupled to a second light source circuit 108 mayemit light in a second spectrum. In another embodiment, laser controlcurrents may be varied such that a single laser emits electromagneticradiation at varying frequencies in different spectrums through a singleoptical fiber.

Using one or methods described herein, the glucose biosensor 100processes the reflected light 132 to determine a glucose levelmeasurement. When a glucose level measurement reaches a predeterminedhigh or low threshold, the glucose biosensor 100 may transmit an alertmessage using the wireless transceiver 126. For example, in general, agood range for blood glucose levels is between 70 milligrams/deciliter(mg/Dl) and 150 mg/Dl. When a detected glucose level is lower than 70 orgreater than 150, the alert message may trigger a request for analternate glucose monitoring method be performed to confirm the glucoselevels, such as a finger prick method. The alert may also triggerwarnings to inject insulin or perform other corrective health measures.In addition, the glucose biosensor 100 may transmit immediate healthalerts when a dangerous level of glucose is detected, such as lower than40 mg/Dl or over 240 mg/Dl. As explained in more detail below, thesealerts may be transmitted by the wireless transceiver 126 to a healthmonitoring gateway that is connected to the Internet. The alerts may betransmitted to a patient's phone, doctor office, caregiver, hospital,pharmacy, etc.

FIG. 2 illustrates another schematic diagram of an embodiment of theglucose biosensor 100. In addition to the light emitter and detectorcircuit 102, the glucose biosensor 100 may include one or more otherbiosensors, such as temperature sensor 212, pulse detector circuit andoximeter circuit 214.

The temperature sensor 212 is configured to detect temperature in theouter ear canal. Temperature fluctuations can be indicative of glucoselevels in the blood stream or a possible warning of an infection. Forexample, a detected temperature change over a predetermined thresholdmay trigger the glucose biosensor 100 to restart glucose monitoring. Inan embodiment, the temperature sensor 212 emits an infrared (IR) lightsignal and process the reflected light 132 to determine a temperaturemeasurement. In another embodiment, the temperature sensor 212 includesan array of sensors (16×16 pixels) positioned within the ear canal tomeasure discrete temperature changes inside the ear drum. Thesetemperature fluctuations may be used for early prediction of infectionor glucose level fluctuations.

The glucose biosensor 100 may also include the pulse detector andoximeter circuit 214. The pulse detector circuit and oximeter circuit214 includes an infrared (IR) pulse oximeter configured to track a pulserate and oxygen levels in the blood of the ear canal. In an embodiment,the pulse detector and oximeter circuit 214 may be used to synchronizethe pulses of emitted light 130 from the light emitter and detectorcircuit 102 with higher or maximum blood flow thru the ear canal area.For example, when the IR pulse oximeter detects a pulse of blood orother indicator of a high or maximum blood flow in the ear canal area,it signals the light emitter and detector circuit 102 to initiate alight pulse for detecting glucose levels.

The glucose biosensor 100 may also include the pressure monitor circuit216. The pressure monitor circuit 216 is configured to monitor bloodpressure through the ear canal using IR reflected light. The pressuremonitor circuit 216 may provide additional local pressurizationinformation. For example, when the blood pressure is higher, itdetermines that a higher blood flow is occurring through the ear canaland provides a possible method for a blood pressure reading.

In an embodiment, the glucose biosensor 100 is battery operated andincludes a battery 210. To help lower power consumption, in anembodiment, the glucose biosensor 100 includes a motion detector circuit218 for monitoring activity. For example, the motion detector circuit218 may include a three-axis accelerometer that measures a position ofthe patient's head and motion from normal activities. When a patient isstill for a predetermined time period, such as during asleep, the motiondetector circuit 218 detects little to no movement and signals theglucose biosensor 100 to enter into a rest mode. In the rest mode, theglucose biosensor 100 stops glucose monitoring and other non-essentialprocessing functions. When the motion detector circuit 218 detectsmovement for another predetermined time period, the motion detectorcircuit 218 signals the glucose biosensor 100 to exit rest mode andresume monitoring. This activity monitoring feature helps to save powerand extend battery life.

In addition, the glucose biosensor 100 may also operate as an activitytracker. The motion detector circuit 218 may determine periods ofactivity and rest. During such periods of activity and rest, the glucosebiosensor 100 determines pulse, oxygen levels, heart rate, core bodytemperature, glucose readings, etc. The processing circuit 120 may storethese measurements with an indicator of activity level in the memory122. These measurements may be used to track biosensor data during suchperiods of activity and rest, e.g. in a fitness tracker application.

FIG. 3 illustrates a schematic drawing of another exemplary embodimentof the glucose biosensor 100. The glucose biosensor 100 includes anouter casing 300 and one or more printed circuit boards (PCB) 302 thatinclude at least the processing circuit 120, memory 122, wirelesstransceiver 126 and the light emitter and detector circuit 102. Theplurality of optical fibers 110, 112 and 114 are optically coupled tothe PCB 302 by a plurality of optical couplers 304, 306 and 308. Theplurality of optical fibers 110, 112 and 114 are encased by an earpiece310. The earpiece 310 is shaped to fit within an outer ear canal. In anembodiment, to help prevent cross contamination, the earpiece 310 or anearpiece cover may be disposable and replaced with a new earpiece 310 orearpiece cover with each use.

FIG. 4 illustrates a schematic drawing of another exemplary embodimentof a glucose biosensor 100. This embodiment of the glucose biosensor 100includes the plurality of optical fibers 110, 112 and 114 and anearpiece 400. The plurality of optical fibers 110, 112, 114 areoptically coupled to the glucose biosensor 100 by the plurality ofoptical couplers 404, 406, 408. In an embodiment, the plurality ofoptical fibers 110, 112 and 114 are preferably sized such that a casing402 of the glucose biosensor 100 may be held while the earpiece 400 ispositioned within the outer ear canal. For example, the plurality ofoptical fibers 110, 112, 114 may be two to three feet long with a 1000uM thickness.

FIG. 5 illustrates a schematic drawing of another exemplary embodimentof a casing 502 for the glucose biosensor 100. In this embodiment, thecasing 502 of the glucose biosensor 100 is configured to attach to aneye glass frame 500. For example, the glucose biosensor 100 includes aclip or other fastener that attaches to a temple 504 of the eye glassframe 500. The optical fibers 110, 112, 114 may then be positioned inthe ear canal without needing to hold the glucose biosensor 100.

FIG. 6 illustrates a schematic drawing of another exemplary embodimentof a glucose biosensor 100. In this embodiment, the glucose biosensor100 is configured as an earpiece 608 shaped to rest around the outerear. The plurality of optical fibers 110, 112, 114 lead from theearpiece 608 to an earbud 600. The ends of optical fibers 110, 112, 114are encased in the earbud 600. The earbud 600 may then be positionedinto an outer ear canal. The earbud 600 may be fabricated from rubber orplastic. The glucose biosensor 100 also includes a battery 602. Forexample, the battery 602 may be a replaceable lithium battery or arechargeable battery.

Since the ear membrane is thin at the back of the ear, a pulse detectorand oximeter circuit 604 may be positioned to detect pulse and oxygenlevels from the back of the ear rather than from the ear canal. Atemperature sensor 612 may also be positioned on the glucose biosensor100 to detect temperature from membranes on the back of the ear.

In another embodiment, the glucose biosensor 100 may be attached to orincluded within a headphone style mechanical interface. The headphonestyle mechanical interface provides comfort while performing glucosemeasurements.

In another exemplary embodiment, the glucose biosensor 100 isencapsulated in a swallowable pill form factor with a wirelesstransceiver. The pill is ingestible and may employ a similar UVfluorophores technique described herein or other techniques to measureglucose level measurements. The glucose level measurements aretransmitted using the wireless transceiver. For example, the ingestiblepill transmits a UV, visible or IR light and measures the internallyreflected light to determine glucose levels. The ingestible pillwirelessly transmits the glucose measurements to a gateway 1100 orglucose meter 1200 outside the body.

FIG. 7 illustrates a logical flow diagram of an exemplary method 700 forglucose monitoring. A light pulse (either UV, visible or IR or acombination thereof) is emitted by a light source circuit andtransmitted by at least one optical fiber into an ear canal. Thereflected light is captured by a plurality of optical fibers, whereineach of the plurality of optical fibers transmits the reflected light toa photodetector circuit. For example, a first optical fiber and a secondoptical fiber capture the reflected light. The reflected light capturedby the first optical fiber is detected by a first photodetector circuit,and the reflected light captured by the second optical fiber is detectedby a second photodetector circuit 704. The reflected light is processedand a glucose level measurement is obtained 706. The glucose levelmeasurement is then wirelessly transmitted to a gateway or glucose meteror user device 708.

FIG. 8 illustrates a logical flow diagram of an exemplary method 800 forglucose monitoring in more detail. As explained hereinabove, the glucosebiosensor 100 obtains a glucose level measurement 802. The glucose levelmeasurement is compared with normal ranges, and it is determined whetherthe glucose level measurement is within predetermined thresholds 804.The thresholds may be configured specifically for the authorized user ofthe glucose biosensor 100 or based on general guidelines for safe rangesof glucose levels in the bloodstream. For example, in general, a saferange for glucose levels is between 70 milligrams/deciliter (mg/Dl) and150 mg/Dl. When the glucose level measurements are within thepredetermined thresholds, the glucose level measurements are wirelesslytransmitted with a time indicator 812.

When the glucose level measurements are not within the predeterminedthresholds, an alert is generated with a request for another glucosetest using an alternative method, such as a finger prick method 806. Thealternative method provides a second test for glucose levels todetermine whether the glucose measurement obtained by the glucosebiosensor is accurate or whether an error has occurred. The second testmay be performed prior to any corrective measures (such as insulininjection, etc.). The glucose level measurement and alert with requestare wireless transmitted to a gateway or glucose meter or user device808. For example, when the glucose measurement is lower than 70 mg/Dl orgreater than 150 mg/Dl, the alert message may include a request for analternate glucose monitoring method be performed to confirm the glucoselevels, such as a finger prick method. The alert may also triggerwarnings to inject insulin or perform other corrective health measures.In addition, the glucose biosensor 100 may transmit immediate healthalerts when a dangerous level of glucose is detected, such as lower than40 mg/Dl or over 240 mg/Dl, with a message advising that the patientperform certain corrective measures, such as injection of insulin. Theimmediate health alert may be transmitted to a gateway, glucose meter, auser device, doctor's office, or other contact person as well.

FIG. 9 illustrates a logical flow diagram of an exemplary method 900 forobtaining a glucose level measurement. To cancel out any foregroundnoise, power values for ambient light in the ear canal are firstobtained 902. For example, prior to emission of a light pulse, ambientlight is captured by a first optical fiber and transmitted to a firstphotodetector circuit. The first photodetector circuit transmits thedetected light signal to an A/D converter circuit that generates a firstdigital signal. From the sampled first digital signal, the minimum,maximum and peak power values of the ambient light are calculated, e.g.using an integral equation of energy. The power values for the ambientlight from the first optical fiber are stored in memory, representedherein as A1. Similarly, prior to a light pulse, the ambient lightcaptured by a second optical fiber is detected by a second photodetectorand an A/D converter circuit generates a second digital signal. From thesecond digital signal, the minimum, maximum and peak power values areare calculated, e.g. using an integral equation of energy. The powervalues for the ambient light from the second optical fiber are stored inmemory, represented herein as A2.

Next, a light pulse, e.g. of approximately 10 ms, is emitted 904, andthe reflected light from a first optical fiber is detected by a firstphotodetector circuit to generate a first detected light and thereflected light from a second optical fiber is detected by a secondphotodetector circuit that generates a second detected light. The firstphotodetector circuit transmits the first detected light to a first A/Dconverter that generates a first digital signal, and the secondphotodetector circuit transmits the second detected light to either thefirst A/D converter or to a second A/D converter to generate a seconddigital signal 906. The minimum, maximum and peak power levels of thefirst digital signal, represented herein as B1, and the second digitalsignal, represented herein as B2, are obtained 908.

The current measurements of the power levels are then compared withprevious measurements 912. When the current measurements are not withina predetermined threshold, e.g. a difference greater than 30% fromprevious measurements, then the current measurements are ignored, andthe measurements are repeated 914. When the current measurements arewithin a predetermined threshold, a glucose level measurement isobtained using the current measurements 916.

An exemplary process for calculating a glucose level measurement is nowexplained through other methods and calculations may also beimplemented. A differential value is calculated between the power levelsderived from the reflected light B1, B2 and the foreground noise A1, A2.For example, a differential channel equation is used to cancel out thepower levels obtained from the detected ambient light A1, A2 from thepower levels obtained using the reflected light B1, B2:

Sum=(B1−A1)−ABS(B2−A2), where ABS is the absolute value.

The above Sum is calculated for a plurality of samples over a shortperiod, e.g. ˜10 ms, and the partial integral of the Sums of the samplesis calculated to generate an interim value. A bit shifting is performedon the interim value for scaling purposes. For example, the interimvalue is right shifted to reduce resolution to allow for small integernumbers like 50-300 mg/Dl. An individual offset may also be applied, asdetermined in a calibration process described in more detail withrespect to FIG. 10, to obtain the glucose level measurement 916.

Another exemplary process for calculating a glucose level measurement isbased on a phase change. For example, the samples B1, B2 of thereflected light have wavelength information as well. In an embodiment, aphase change between the emitted light and the samples B1 and B2 isdetermined. For example, using a fast sample A/D conversion, phaseinformation for the samples B1 and B2 are stored in a matrix. The phaseinformation is compared to the emitted light from the light source. Thephase response curves for each channel, e.g. each photodetector, is thendetermined. A glucose level measurement is then determined based on thephase response curves.

Though two exemplary processes for calculating a glucose levelmeasurement is described herein, e.g. one using power levels and theother based on phase changes, other methods and calculations may also beimplemented. In addition, both these exemplary processes may beimplemented in combination to obtain a glucose level measurement 916.

Next, the process then determines whether additional measurements arescheduled 918. For example, in an embodiment, the process is repeatedover three 10 ms intervals followed by a 30-60 second rest period. Whenadditional measurements are scheduled, the measurements are repeated914. When additional measurements are not scheduled, the process entersa rest period 920.

FIG. 10 illustrates a logical flow diagram of an embodiment of anexemplary method 1000 for calibrating the glucose biosensor 100 forglucose monitoring. A reliable glucose level measurement is received1002. For example, a finger prick method may be used with a glucosemeter to determine a glucose level. This measurement is wirelesslytransmitted to the glucose biosensor 100 by the glucose meter or agateway. A glucose level measurement is then obtained by the glucosebiosensor from the ear canal 1004. The ear canal measurement is comparedwith the reliable measurement. An absolute difference or a percentagedifference is determined 1006. This process may be repeated a number oftimes. Based on the determined difference, a calibration is calculated1008. This calibration is used by the glucose biosensor 100 to adjustthe glucose level measurement from the ear canal, e.g. as describedabove with respect to FIG. 9.

Gateway

FIG. 11 illustrates a schematic drawing of an exemplary embodiment of agateway 1100. The gateway 1100 includes a processing circuit 1102 and amemory 1104. For example, the memory 1104 is a non-transitory, processorreadable medium that stores instructions which when executed by theprocessing circuit 1102, causes the processing circuit 1102 to performone or more functions described herein. The memory 1104 may also storebiosensor data 1124 from the glucose biosensor 100.

The gateway 1100 includes a wireless gateway transceiver 1108 operableto wirelessly communicate with the glucose biosensor 100. For example,the wireless gateway transceiver 1108 may operate in the 900 MHz rangeover a serial link using a proprietary protocol or may utilize astandard protocol, such as IEEE 802.11ah, IEEE 802.15-11, or Zigbee, tocommunicate with the glucose biosensor 100. In other embodiments, thewireless gateway transceiver 1108 may operate in one or more otherwireless frequency bands or protocols, such as near field communication,short range radio frequency, RFID, infrared link, Bluetooth, or othershort range wireless communication protocol, to communicate with theglucose biosensor 100.

The gateway 1100 receives packets with biosensor data 1124, includingglucose level measurements, from the glucose biosensor 100 using thewireless gateway transceiver 1108. The gateway 1100 stores and tracksthe biosensor data 1124. When two or more authorized patients areoperating biosensors, the wireless gateway transceiver 1108 may requestto receive patient ID information in the data packets with the biosensordata 1124. The gateway 1100 is then operable to store and trackbiosensor data 1124 associated with two or more patients.

The gateway 1100 further includes a network transceiver 1110 that isoperable to communicate either wirelessly or through a wired connectionover a wide area network (WAN), such as the Internet, to a doctor'soffice, hospital, pharmacy, caregiver, user device or a device ofanother authorized user. The gateway 1100 may further communicate with acentral application server over the WAN that provides health monitoringservices. The gateway 1100 may communicate biosensor and patient data tothe central application server for access by a user device, such as asmart phone, laptop, desktop, smart tablet, etc., as described in moredetail herein. The gateway 1100 further includes a display 1114. Thedisplay 1114 may be a touch screen.

In an embodiment, the gateway 1100 is operable to support a healthmonitoring application 1112. The health monitoring application 1112 maybe a web-based application supported by a central application server.For example, the central application server may be a web server andsupport the health monitoring application 1112 via a website. Thegateway 1100 may then use a web browser or other HTML enabledapplication to access either all or parts of the health monitoringapplication 1112 via the website. The health monitoring application 1112is then run within the the web browser. In another embodiment, thehealth monitoring application 1112 is a stand-alone application that isdownloaded to the gateway 1100 and is operable on the gateway 1100without access to a web server or only needs to accesses a web serverfor additional information, such as biosensor data.

Using the health monitoring application 1112, the gateway 1100 isconfigured to provide a graphical user interface (GUI) for the display1114. An authorized user is operable to track biosensor data 1124 usingthe health monitoring application 1112 and control certain functions ofthe glucose biosensor 100. For example, the health monitoringapplication 1112 may generate a GUI that includes a graphical selectionof commands for controlling the glucose biosensor 100, such as a restmode command or re-calibrate command. The authorized user may inputcommands to control the operation of the glucose biosensor 100 or otherbiosensors. In other methods, the gateway 1100 may include voiceinteractive capabilities to communicate alerts and receive data orcommands.

In addition, the health monitoring application 1112 may generate a GUIthat includes a graphical display of glucose levels or other biosensordata 1124 over a requested period of time, such as one day, one week,etc. The health monitoring application 1112 may issue alerts whenbiosensor data 1124 reaches certain predetermined thresholds. Forexample, when a blood glucose level reaches a predetermined high or lowthreshold, the gateway 1100 displays an alert and sounds an alertmessage. In general, a good range for blood sugar levels is between 70milligrams/deciliter (mg/Dl) and 150 mg/Dl. When the sugar level arelower than 70 mg/Dl or greater than 150 mg/Dl, the alert message mayinclude a request for an alternate glucose monitoring method beperformed to confirm the glucose levels, such as a finger prick method.The alert may also trigger warnings to inject insulin or perform othercorrective health measures. In addition, the glucose biosensor 100 maytransmit immediate health alerts when a dangerous level of glucose isdetected, such as lower than 40 mg/Dl or over 240 mg/Dl. The immediatehealth alert may be transmitted to a user device, doctor's office, orother contact person as well.

The gateway 1100 may also generate a GUI that allows a user to inputdata, such as glucose measurements determined by the finger prickmethod. Such measurements may be communicated back to the glucosebiosensor 100 for calibration using the wireless gateway transceiver1108.

In another example, the gateway 1100 generates a GUI that allows a userto input when a meal is consumed by the patient. Since glucose targetsdepend on timing of meals, this information may be used in the trackingand charting of glucose levels. For example, the American DiabetesAssociation suggests the following targets for most nonpregnant adultswith diabetes. More or less stringent glycemic goals may be appropriatefor each individual: Before a meal (preprandial plasma glucose): 80-130mg/dl and 1-2 hours after beginning of the meal (Postprandial plasmaglucose): Less than 180 mg/dl.

The gateway 1100 may also generate a GUI that includes an activitytracker display. The activity tracker display may include periods ofrest or sleep and periods of activity along with biosensor data for suchperiods, such as pulse, glucose levels, oxygen levels, temperature,blood pressure, etc. One or more of these functions of the healthmonitoring application 1112 described with respect to the gateway mayalso be accessed by a user device using a web-based applicationsupported by the central application server as discussed in more detailherein.

The gateway 1100 may also include an integrated blood glucose meter or aglucose meter receptacle 1106 for interfacing with a blood glucosemeter. For example, the glucose meter may be used in the finger prickmethod to determine blood glucose levels. In an embodiment, the glucoselevel measurement from the glucose biosensor 100 is used as anindicator, e.g. for tracking and charting glucose levels over a periodof time, while readings from the glucose meter using test strips (e.g.finger prick method) are used for more accurate measurements orverification. For example, the glucose level measurements of the glucosemeter are used for verification of the glucose level measurements of theglucose biosensor 100.

The gateway 1100 may include a medicine bottle receptacle 1008. Themedicine bottle receptacle is configured to hold a medicine bottle thatincludes, e.g., glucose test strips. In the finger prick method, thepatient must then prick a clean fingertip with a special needle (lancet)to draw a drop of blood. The test strip is then touched to the drop ofblood and inserted into the glucose meter. The glucose meter determinesthe blood glucose level and displays the measurement on its screen or onthe display 1114 of the gateway 1100. When used and stored properly,blood glucose meters are generally accurate in measuring glucose levels.Thus, the finger prick method provides a good verification of theglucose biosensor 100 measurements.

In an embodiment, the gateway 1100 includes a medicine trackingapplication 1116 and a scale 1118 as part of the medicine bottlereceptacle. The scale 1118 weighs the medicine bottle, and based on theweight, the medicine tracking application 1116 determines a number ofavailable test strips. When the detected number of test strips fallsbelow a threshold, the medicine tracking application 1116 may issue analert to re-order test strips, such as provide a GUI on the display 1114with alert message of the low medication. In another embodiment, thegateway 1100 may communicate with a pharmacy to request a refill. Inanother embodiment, the gateway 1100 may communicate with a doctor'soffice to request a new prescription. The medicine tracking application1116 thus tracks the weight of a medicine bottle or other receptacle andtriggers an alert when the weight reaches a predetermined threshold,e.g. indicating that the medicine needs to be refilled.

The gateway 1100 in an exemplary embodiment may also include an alarmclock and/or a radio 1120. The gateway 1100 may also include an actuatorinterface 1122 for use with a regulated insulin pump or artificialpancreas. The gateway 1100 may receive a glucose level measurement fromthe glucose biosensor 100 or from a glucose meter and process themeasurement to control a regulated insulin reservoir (such as an insulinpump or artificial pancreas) in implants or automatic insulin controlsystem.

FIG. 12 illustrates a schematic block diagram of an exemplary embodimentof the gateway 1100. The gateway 1100 in this embodiment includes aglucose meter receptacle 1202 configured to interface with a stand-aloneglucose meter 1200. In another embodiment, the gateway 1100 may includean integrated glucose meter 1200. The gateway 1100 in this illustrationincludes the medicine bottle receptacle 1208 with a medicine bottle 1210situated therein. The gateway 1100 also includes the display 1114configured to display one or more of the GUI's described herein withrespect to the health monitoring application 1112 or medicine trackingapplication 1116. The gateway 1100 may also include the clock and/orradio 1120.

FIG. 13 illustrates a schematic block diagram of an exemplary embodimentof the glucose meter 1200. The glucose meter 1200 includes a processingcircuit 1302 and a memory 1304. For example, the memory 1304 is anon-transitory, processor readable medium that stores instructions whichwhen executed by the processing circuit 1302, causes the processingcircuit 1302 to perform one or more functions described herein. Thememory 1304 may also store biosensor data 1124 from the glucosebiosensor 100 or generated by the glucose meter 1200 itself.

When the glucose meter 1200 is not integrated with the gateway 1100, theglucose meter 1200 may include a wireless transceiver 1306 operable towirelessly communicate with the glucose biosensor 100 and/or the gateway1100. For example, the wireless transceiver 1306 may operate in the 900MHz range over a serial link using a proprietary protocol or may utilizea standard protocol, such as IEEE 802.11ah, IEEE 802.15-11, or Zigbee,to communicate with the glucose biosensor 100 or the gateway 1100. Inother embodiments, the wireless transceiver 1306 may operate in one ormore other wireless frequency bands or protocols, such as near fieldcommunication, short range radio frequency, RFID, infrared link,Bluetooth, or other short range wireless communication protocol, tocommunicate with the glucose biosensor 100 or the gateway. The glucosemeter 1200 receives packets with biosensor data 1124, including glucoselevel measurements, from the glucose biosensor 100 or the gateway 1100using the wireless transceiver 1306. In addition, the glucose meter 1200transmits packets with biosensor data, including glucose levelmeasurements, to the gateway 1100. The glucose meter 1200 may alsoreceive glucose level measurements directly from the glucose biosensor100 or indirectly through the gateway 1100 and store the data fortracking and display. For example, the glucose meter 1200 may track anddisplay the time and date of a test, the result, and graph trends overtime.

The glucose meter 1200 may also communicate with the glucose biosensor100 to transmit glucose level measurements to the glucose biosensor 100.In an embodiment, the glucose level measurements from the glucosebiosensor 100 are used as an indicator, e.g. for tracking and chartingglucose levels over a period of time, while readings from the glucosemeter 1200 are used for verification since the measurements from theglucose meter 1200 may be more accurate or exact. In another embodiment,as described in FIG. 10, the glucose meter 1200 is used for calibratingmeasurements by the glucose biosensor 100.

The glucose meter 1200 further includes a test strip receptacle 1308 anda strip sensor 1310. In the finger prick method, the patient must pricka clean fingertip with a special needle (lancet) to draw blood. The teststrip is then touched to the blood and inserted into the test stripreceptacle 1308 of the glucose meter 1200. The strip sensor 1310determines the blood glucose level from the test strip and displays themeasurement on display 1312 or on the display 1114 of the gateway 1100.The glucose meter 1200 may further include a user interface 1316, suchas a keypad, to control operation and the display 1312 of the glucosemeter 1200. The glucose meter 1200 may be battery operated and include abattery 1318.

One or more functions described herein as being performed by the glucosemeter 1200 may be performed by the gateway 1100. Alternatively, one ormore functions described herein as being performed by the gateway 1100may be performed by the glucose meter 1200.

Communication Network

FIG. 14 illustrates a schematic block diagram of an embodiment of anexemplary communication network 1420 in which the devices describedherein may operate. The exemplary communication network 1420 includesone or more networks that are communicatively coupled, such as a widearea network (WAN) 1422, a local area network (LAN) 1424, a firstwireless local area network (WLAN) 1426 a, a second WLAN 1426 b, and awireless wide area network (WAN) 1428. The LAN 1424 and the first andsecond WLANs 1426 a and 1426 b may operate inside a home or enterpriseenvironment, such as a doctor's office, pharmacy or hospital or othercaregiver or business. The wireless WAN 1428 may include, for example, a3G or 4G cellular network, a GSM network, a WIMAX network, an EDGEnetwork, a GERAN network, etc. or a satellite network or a combinationthereof. The WAN 1422 includes the Internet, service provider network,other type of WAN, or a combination of one or more thereof.

One or more gateways 1100 a, 1100 b, 1100 c, 1100 d are communicativelycoupled to a central application server 1400 by one or more of theexemplary networks in the communication network 1420. The centralapplication server 1400 includes a network interface circuit 1402 and aserver processing circuit 1404. The network interface circuit 1402includes an interface for wireless and/or wired network communicationswith one or more of the exemplary networks in the communication network1420. The network interface circuit 1402 may also include authenticationcapability that provides authentication prior to allowing access to someor all of the resources of the central application server 1400. Thenetwork interface circuit 1402 may also include firewall, gateway andproxy server functions.

The central application server 1400 also includes a server processingcircuit 1404 and a memory device 1406. For example, the memory device1406 is a non-transitory, processor readable medium that storesinstructions from the health monitoring server application 1408 whichwhen executed by the server processing circuit 1404, causes the serverprocessing circuit 1404 to perform one or more functions describedherein. In an embodiment, the memory device 1406 stores biosensor datafor a plurality of patients transmitted to the central applicationserver 1400 from the plurality of gateways 1100 a-d.

The central application server 1400 includes a health monitoring serverapplication 1408. The health monitoring server application 1408 isoperable to communicate with the plurality of gateways 1100 a-d and witha plurality of user devices 1416 a-c to communicate with and support thehealth monitoring applications 1112 residing on the plurality ofgateways 1100 a-d. The health monitoring server application 1408 may bea web-based application supported by the central application server1400. For example, the central application server 1400 may be a webserver and support the health monitoring server application 1408 via awebsite. In another embodiment, the health monitoring application 1112is a stand-alone application that is downloaded to the gateways 1100 a-dby the central application server 1400 and is operable on the gateways1100 a-d without access to the central application server 1400 or onlyneeds to accesses the central application server 1400 for additionalinformation, such as biosensor data. Using the health monitoringapplication 1112, the gateways 1100 a-d are configured to to trackbiosensor data 1124 and control certain functions of the gateways 1100a-d and any associated glucose biosensors 100. In addition, the healthmonitoring server application 1408 supports a user application on one ormore user devices 1416 a, 1416 b, 1416 c, as described in more detailwith respect to FIG. 15.

The central application server 1400 may also be operable to communicatewith a doctor's office, pharmacy or hospital or other caregiver orbusiness 1418 over the communication network 1420 to provide biosensordata and alerts. For example, one or more of the gateways 1100 a-d maycommunicate messages including biosensor data, health alerts, requestsfor medicine refills or requests for new prescriptions to the healthmonitoring server application 1408. The health monitoring serverapplication 1408 may then transmit the messages to a doctor's office,pharmacy or hospital or other caregiver or business 1418 over thecommunication network 1420 as requested or needed.

User Device

FIG. 15 illustrates a schematic block diagram of an embodiment of theuser device 1416. The user device 1416 may include a smart phone,laptop, desktop, smart tablet, smart watch, or any other personal userdevice. In an embodiment, the user device 1416 includes a processingcircuit 1502, a display 1504 and a memory 1506. For example, the memory1506 is a non-transitory processor readable memory that storesinstructions which when executed by the processing circuit 1502, causesthe processing circuit 1502 to perform one or more functions describedherein. The user device 1416 includes a wireless transceiver that isconfigured to communicate over the communication network 1420 to thecentral application server 1400 or to one or more gateways 1100.

The user device 1416 further includes a user application 1508. The userapplication 1508 may be a web-based application supported by the centralapplication server 1400. For example, the central application server1400 may be a web server and support the user application 1508 via awebsite. The user device 1416 may then use a web browser or other HTMLenabled application to access either all or parts of the userapplication 1508 via the website supported by the central applicationserver 1400. The user application 1508 is then run within the the webbrowser. In another embodiment, the user application 1508 is astand-alone application that is downloaded to the user device 1416 andis operable on the user device 1416 without access to the web server oronly needs to accesses the web server for additional information, suchas biosensor data. In another embodiment, the user application 1508 maybe a mobile application designed for download and use by a mobile phoneor other mobile device.

The user application 1508 is configured to control certain functions ofthe glucose biosensor 100. For example, the user application 1508 maygenerate a GUI 1512 on the display 1504 that includes a graphicalselection of commands for controlling the glucose biosensor 100, such asa rest mode command or re-calibrate command. The authorized user mayinput commands into the user device 1416 to control the operation of theglucose biosensor 100, glucose meter 1200 or other biosensors.

In addition, the user application 1500 is configured to track anddisplay biosensor data. For example, the user application 1500 receivesbiosensor data from the central application server 1400 or directly froma glucose biosensor 100 or gateway 1100 and stores the biosensor data.The user application 1500 may then upon request generate a GUI 1512 thatincludes a graphical display of glucose levels or other biosensor dataover a requested period of time, such as one day, one week, etc. Theuser application 1508 may issue alerts when biosensor data reachescertain predetermined thresholds. For example, when the user device 1416receives notice of a glucose level measurement from the centralapplication server 1400 or a gateway 1100 that reaches or exceeds apredetermined high or low threshold, the user application 1508 displaysand sounds an alert message. In general, a good range for blood sugarlevels is between 70 milligrams/deciliter (mg/Dl) and 150 mg/Dl. Whenthe sugar level are lower than 70 mg/Dl or greater than 150 mg/Dl, thealert message may include a request for an alternate glucose monitoringmethod be performed to confirm the glucose levels, such as a fingerprick method. The alert may also trigger warnings to inject insulin orperform other corrective health measures. In addition, the user device1416 may transmit immediate health alerts when a dangerous level ofglucose is detected, such as lower than 40 mg/Dl or over 240 mg/Dl and amessage with advice that the patient performs certain correctivemeasures, such as injection of insulin.

The user application 1508 may also generate a GUI 1512 that allows auser to input data, such as glucose measurements determined by thefinger prick method. Such measurements may be communicated back to theglucose biosensor 100 for calibration and to the central applicationserver 1400 for storage.

In another example, the user application 1508 generates a GUI 1512 thatallows a user to input when a meal is consumed by the patient. Sinceglucose targets depend on timing of meals, this information may be usedin the tracking and charting of glucose levels. For example, theAmerican Diabetes Association suggests the following targets for mostnonpregnant adults with diabetes. More or less stringent glycemic goalsmay be appropriate for each individual: Before a meal (preprandialplasma glucose): 80-130 mg/dl and 1-2 hours after beginning of the meal(Postprandial plasma glucose): Less than 180 mg/dl.

The user application 1508 may also track activity and generate one ormore GUIs 1512 on the display 1504 that includes an activity trackerdisplay. The activity tracker display may include periods of rest orsleep and periods of activity along with biosensor data for suchperiods, such as pulse, glucose levels, oxygen levels, temperature,blood pressure, etc.

FIG. 16 illustrates a schematic block diagram of an embodiment of agraphical user interface (GUI) 1600 generated by the user application1508. The user application 1508 may generate the GUI 1600, e.g. on theuser device. The GUI 1600 provides an interface for a personalauthorized user, pharmacy or physician to login and use the application.

FIG. 17 illustrates a schematic block diagram of another embodiment of agraphical user interface (GUI) 1700 generated by the user application1508. The user application 1508 may generate the GUI 1700, e.g. on theuser device. The GUI 1700 provides an interface for monitoring glucoselevels of a patient. The GUI 1700 illustrates a history of readings ofglucose level measurements 1702. The history may display one day,multiple days, one week, month, or a specified time frame. The userapplication 1508 also tracks a recommended time for a next glucose levelmeasurement. The user application 1508 displays the next reading time1704 in the GUI 1700. The user application 1508 may also display anumber of glucose test strips remaining 1706. The number of glucose teststrips may be determined using the scale and weight of a test stripmedicine bottle or based on a number of glucose level measurementsreceived from the glucose meter 1200. The user application 1508 is alsoconfigured to display current data 1708.

FIG. 18 illustrates a schematic block diagram of another embodiment of agraphical user interface (GUI) 1800 generated by the user application1508. The user application 1508 may generate the GUI 1800, e.g. on theuser device. The GUI 1800 illustrates a history of readings of glucoselevel measurements and insulin dosages. For example, the GUI 1800illustrates a last reading of a glucose level measurement 1802 and atime of the last insulin dosage 1804. The GUI 1800 illustrates agraphical representation of glucose levels 1806 over a selected periodof time. The GUI may also illustrate a pie chart or other graphicalrepresentation of minimum, maximum and average glucose levelmeasurements 1808 over a selected period of time. The GUI 1800 furtherillustrates a history of insulin dosages 1812 over a selected period oftime and an overview of the total number of injections, average numberof injections or maximum number of injections over a selected period oftime 1810.

The GUI 1800 may indicate whether a glucose level measurement is fromthe glucose meter 1200 or from the glucose biosensor 100. For example,in an embodiment, the glucose level measurement from the glucosebiosensor 100 is used as an indicator, e.g. for tracking and chartingglucose levels over a period of time, while readings from the glucosemeter 1200 are used for more accurate measurements or verification.

FIG. 19 illustrates a schematic block diagram of another embodiment of agraphical user interface (GUI) 1900 generated by the user application1508. The user application 1508 may generate the GUI 1900, e.g. on theuser device. The GUI 1900 provides an interface for ordering glucosetest strips. The user application 1508 may generate a request or alert,and then the GUI 1900 alert when a number of glucose test stripsremaining is less than a predetermined threshold. The test strips maythen be re-ordered using the GUI 1900.

The glucose monitoring system thus provides reliable, non-invasiveoptical measurements of glucose levels. This non-invasive method may beused with humans or animals without requiring numerous painful fingerpricks throughout a day.

Exemplary Embodiments of the Analytic Biosensor

The above described embodiment of a glucose biosensor 100 still requirescalibration using a glucose meter 1200. For example, frequent, evendaily calibration with a glucose meter 1200 is sometimes required, andthereby compounds the potential for errors and possible infections. Thisproblem of daily calibration has been difficult to overcome due tovarious factors including blood emissivity types, tissue colorvariances, temperature, and even manufactured insulin inducedbio-chemical reaction.

In an embodiment, an analytic biosensor is configured to performmonitoring of biometric analytical markers, including glucose levels,using a combination of two or more non-invasive techniques that analyzelight reflected from an ear canal. For example, the techniques mayinclude: near infrared spectroscopy, Raman spectroscopy,flourophoresence, thermal emissions, photoacoustic and polarimetry. Inuse, two or more of the techniques are employed to obtain biometricmeasurements. An average or mean of the biometric measurements from thetwo or more techniques are then used for calibration of the analyticbiosensor. The analytic biosensor is also configured to non-invasivelymeasure other biometric data, such as pulse rate, blood pressure,peripheral oxygen (SpO2) saturation amounts, body temperature, variouselectrolytes and many common blood analytic levels, such as bilirubinamount.

FIG. 20 illustrates a schematic block diagram of an exemplary embodimentof the analytic biosensor 2000. The analytic biosensor 2000 includes aprocessing circuit 2002 and a memory 2004. For example, the memory 2004is a non-transitory processor readable memory that stores instructionswhich when executed by the processing circuit 2002, causes theprocessing circuit 2002 to perform one or more functions describedherein. The analytic biosensor 2000 includes a wireless transceiver 2006that is configured to communicate with one or more gateways 1100,similarly as described herein with respect to the glucose biosensor 100.For example, the wireless transceiver 2006 may operate in the 900 MHzrange over a serial link using a proprietary protocol or may utilize astandard protocol in the 900 MHz range, such as IEEE 802.11ah, Zigbee,IEEE 802.15-11 etc. In other embodiments, the wireless transceiver 2006operates in one or more other wireless frequency bands or protocols,such as near field communication, short range radio frequency, RFID,infrared link, Bluetooth, or other short range wireless communicationprotocol.

The analytic biosensor 2000 also includes a light emitter and detectorcircuit 2010 having a plurality of light sources. For example, theanalytic biosensor 2000 includes a visible light source 2012, a UV lightsource 2018 and an IR light source 2022. The visible light source 2012is configured to emit light across a broad spectrum of frequencies andincludes, e.g. a tri-color LED, such as an (RGB) LED 2014, wherein eachcolor of the LED is controlled separately. In an embodiment, a drivercircuit 2026 is configured to drive each lead or color of the RGB LED2014 separately to generate a broad spectrum of colors to performvarious non-invasive measurement techniques, as described furtherherein. A light collimator 2016, such as a prism, may be used to align adirection of the light emitted from the RGB LED 2014. The analyticbiosensor 2000 also includes a UV light source 2018 and an associateddriver circuit 2020, and an IR light source 2022 and an associateddriver circuit 2024. The plurality of light sources are thus configuredto emit frequencies of light across a plurality of classes in theelectromagnetic spectrum, including UV, visible and IR light.

The analytic biosensor 2000 includes one or more optical fibers 2050 fortransmitting emitted light 2026 from the plurality of light sources intoan ear canal. A single optical fiber 2050 may be used for all or some ofthe plurality of light sources or a different optical fiber may be usedfor each of the plurality of light sources.

The light emitter and detector circuit 2010 further includes a pluralityof photodetector circuits, including at least a first photodetectorcircuit 2030 and a second photodetector circuit 2032. The firstphotodetector circuit 2030 and the second photodetector circuit 2032include, for example, one or more photodiodes, phototransistors or othercomponents operable to detect IF, visible and UV light. The firstphotodetector circuit 2030 and the second photodetector circuit 2032 mayalso include a first spectrometer 2034 and a second spectrometer 2036,respectively. The first spectrometer and the second spectrometer detectan intensity of light as a function of wavelength or of frequency. Thespectrometers 2034, 2036 are thus each able to perform a spectrumanalysis of the reflected light. The first photodetector circuit 2030and the second photodetector circuit 2032 are coupled to a first A/Dcircuit 2038 and a second A/D circuit 2040. Alternatively, a single A/Dcircuit may be coupled to both the first and second photodetectorcircuits.

The light emitter and detector circuit 102 is optically coupled to aplurality of optical fibers 2052, 2054 for capturing reflected lightfrom the ear canal. In an embodiment, the plurality of optical fibers2052, 2054 includes at least a first optical fiber 2052 opticallycoupled to the first photodetector circuit 2030 and a second opticalfiber 2054 optically coupled to the second photodetector circuit 2032.Other configurations and numbers of optical fibers may also be employedfor capturing the reflected light.

The plurality of optical fibers 2050, 2052 and 2054 are encased withinan earpiece or ear bud or other casing that is configured to fit withinan outer ear canal of a patient. In an embodiment, the one or moreoptical fibers 2050 optically coupled to the plurality of light sources2012, 2018, 2022 are configured to rest within the middle of the opticalfibers 2052, 2054 coupled to the photodetector circuits, 2030, 2032.However, other configurations and numbers of the plurality of opticalfibers 2050, 2052, 2054 may also be implemented.

In use, analytic biosensor 2000 performs a plurality of non-invasivetechniques that analyze light reflected from an ear canal. For example,the techniques may include: infrared absorption spectroscopy, Ramanspectroscopy, thermal emission spectrometry, flourophoresence, andphotoacoustic spectrometry. Various techniques that may be performed bythe analytic biosensor 2000 are now described in more detail.

Infrared Absorption Spectroscopy

Infrared absorption spectroscopy is used to provide rapid, non-invasiveanalysis of a wide range of sample types. This method is based on theprinciple that every type of molecule has resonance absorption peakswhich are directly related to the molecule's concentration in a sample.Thus, reflected radiation from a sample can be analyzed to determine theconcentration of glucose and other electrolytes.

In an embodiment, the IR light source 2022 emits a near-IR light that istransmitted by at least one optical fiber 2050 into an ear canal. Aplurality of optical fibers 2052, 2054 capture the reflected light andtransmit the reflected light 2042 to the first photodetector circuit2030 and the second photodetector circuit 2032. The first photodetectorcircuit 2030 and the second photodetector circuit 2032 detect thereflected light and generate an analog signal. The processor analyzesthe reflected light to determine the resonance absorption peaks of thereflected light. The determined resonance absorption peaks are comparedwith the expected resonance absorption peaks for analyte to obtain ananalytic concentration measurement. For example, the resonanceabsorptions peaks are analyzed with the expected resonance absorptionpeaks for glucose to obtain a glucose level measurement. The expectedresonance absorption peaks for pure glucose are determined in the midinfrared ranging from 2.5 μm to about 16 μm along with their magnitudesto be about 75 peaks in the above range with different peak absorptionvalues.

In another embodiment, by comparing the ratio of light absorption fromtwo different frequencies, e.g. 430 nm (Blue Light) and 940 nm (IRLight), a ratio of glucose levels can be calculated based on theBeer-Lambert law. The spectrum of pure glucose can be determined at awavelength, so the molar attenuation coefficient ε at that wavelengthcan be determined. For example, measurements of decadic attenuationcoefficient μ₁₀ are made at one wavelength λ (e.g. at approximately 430nm). This wavelength of 430 nm has been determined as nearly unique forglucose. Next, a second wavelength (e.g. at approximately 940 nm) isthen used in order to correct for possible interferences. Theconcentration c is then given by:

$c = {\frac{\mu_{10}(\lambda)}{ɛ(\lambda)}.}$

A glucose level measurement can thus be obtained using infraredabsorption spectroscopy.

Raman Spectroscopy

When radiation has an impact upon a sample, most of the incident lightsuffers Rayleigh scattering and a small portion of light undergoesfrequency shifts. The measurement of these frequency shifts is known asRaman spectroscopy. Raman spectroscopy may provide a spectral signaturethat is less influenced by water than near-infrared absorptionspectroscopy.

In an embodiment, the RGB LED 2014 is used as a light source for Ramanspectroscopy. The use of three independent controlled drivers enablesthe RGB LED 2014 to have a broad frequency spectrum. Additionally, thelight collimator in front of the RGB LED 2014 may be used to provide auniform wave front to minimize any dominant peaks across the frequencyrange of the emitted light 2026.

In an embodiment, the RGB LED 2014 emits a light across a predeterminedfrequency range that is transmitted by at least one optical fiber 2050into an ear canal. A plurality of optical fibers 2052, 2054 capture thereflected light and transmit the reflected light 2042 to the firstphotodetector circuit 2030 and the second photodetector circuit 2032.The first spectrometer and the second spectrometer 2036 each determine afrequency shift in the reflected light from the predetermined frequencyrange of the emitted light. The processor analyzes the frequency shiftof the reflected light 2042 from the emitted light 2026 to obtain ananalytic concentration measurement, for example, a glucose levelmeasurement.

Thermal Emission Spectrometry

Thermal emission Spectrometry (TES) is based on the principle thatnatural mid-infrared emission from the human body, especially thetympanic membrane in the ear canal, is modulated by the state of theemitting tissue. Radiation from the human body possesses informationabout spectral characteristics of the object and is determined byabsolute body temperatures as well as by the properties and states ofthe emitting body tissue.

One can measure radiation from the skin of the human body or, morereliably, quantify the infrared emission from the tympanic membrane. Thetympanic membrane is known to be in an excellent position to measure,for example, body temperature because it shares the blood supply withthe hypothalamus, the center of core body temperature regulation. Thetympanic thermometer measures the integral intensity of infraredradiation in the ear canal. It is inserted into the ear canal so as tosufficiently enclose the detector apparatus such that multiplereflections of radiation from the tympanic membrane transform theauditory canal into a “black body” cavity, a cavity with emissivitytheoretically equal to one. In such a way a sensor can get a clear viewof the tympanic membrane and its blood vessels for measuring the amountof infrared radiation emitted by the patient's tympanic membrane. Thisinfrared radiation is spectrally modified by the tissue when comparedwith the theoretical “black body” radiation as shown in Planck andKirchhoff's law. Thus infrared radiation has the spectralcharacteristics of, for example, the blood in the tympanic membrane ofthe ear canal. This allows measurements of the concentration of bloodconstituencies by spectral analysis of infrared radiation naturallyemitted from the human body.

A sensor inserted in the ear canal can clearly obtain a view of themembrane and its blood vessels to measure the emitted IR radiation. See,e.g., U.S. Pat. No. 5,823,966, entitled, “Non-invasive continuous bloodglucose monitoring,” issued on Oct. 20, 1998, which is incorporated byreference herein. It describes that a spectral characteristic of variousconstituencies of the tissue will be separated using non-dispersivecorrelation spectroscopy methods. It relies on the use of a negativecorrelation filter placed in front of an infrared detector. The negativecorrelation filter blocks radiation in the absorption bands for theanalyte to be measured at one of the infrared detector windows when theother infrared detector window is covered by another filter capable ofblocking radiation in such a way that does not include absorption bandscharacteristic for the analyte at all wavelengths in the range ofinterest. Distinguishing the radiation intensity between two detectorwindows, which is done on the detector level because of the physicalconstruction of the detector, provides a measure proportional to toobtain an analytic concentration measurement, for example, a glucoselevel measurement.

In an embodiment, naturally reflected IR light from the ear canal of apatient is captured by a plurality of optical fibers 2052, 2054. Thereflected IR light includes the infrared radiation naturally emitted bythe human body. No light source is used prior to detecting thisnaturally emitted IR light. The first photodetector circuit 2030includes an infrared detector with an IF filter sensitive to an IRglucose signature. The second photodetector circuit 2032 measures theintensity of the reflected IR light without such IF filter. Theprocessor then determines a ratio of intensities of the reflected lightdetected by the first photodetector circuit 2030 and the secondphotodetector circuit 2032. The ratio provides a measure proportional tothe analytic concentration of glucose.

A glucose level measurement can thus be obtained using thermal emissionspectroscopy.

Fluorescence

Fluorescence is a property present in certain molecules, calledfluorophores, in which they emit a photon shortly after absorbing onewith a higher energy wavelength. Fluorescence may be used to measure theconcentration of glucose using a fluorophores, such as one or moresensitive proteins that have been found in glucose. The glucoseconcentration is translated into a power or energy level in thefluorescence.

One particular technique for fluorescence-based non-invasive glucosemonitoring is based on the measurement of cell auto-fluorescence due tothe compound NAP(P)H and signaling of changes in extracellular glucoseconcentrations by fluorescent markers of mitochondrial metabolism. Inone example, fluorescent emissions in the range of 430 nm have beendetected and used to develop correlations to glucose concentrations.

In an embodiment, the visible light source 2012 emits light in the 430nm range that is transmitted by at least one optical fiber 2050 into anear canal. A plurality of optical fibers 2052, 2054 capture thereflected light and transmit the reflected light 2042 to the firstphotodetector circuit 2030 and the second photodetector circuit 2032.The first photodetector circuit 2030 and the second photodetectorcircuit 2032 detect the reflected light 2042 and determine a power orenergy level of the fluorescent emission in the 430 nm range in thereflected light 2042. The processor analyzes the fluorescent emission ofthe reflected light 2042 and correlates the fluorescent emission to aglucose concentration to obtain a glucose level measurement.

A glucose level measurement can thus be obtained using fluorescence.

Photoacoustic Spectrometry

When incoming light is modulated, the absorbing sample warms and coolsin a cycle. If the cycle is fast enough and the sample does not havetime to expand and contract in response to the modulated light, a changein pressure develops. This pressure “wave” can lead to production ofsound waves. These sounds waves can be detected by a sensitivemicrophone or piezoelectric elements. Likewise these sound waves canalso be detected by optical methods using the deflection of light.Modulation frequencies can vary from single digit to thousands of hertz.The light to sound interaction can be used to determine several bloodmarkers as well as indicators in other areas, such as glucose. Thespecific generated sound waves may be correlated to specific key bloodmarkers. The ear drum is ideal to receive and transmit acoustic signalsfor pressure changes. Specific audio tones injected into the ear drum aswell as specific optical signals can be monitored to detect bloodmarkers.

In an embodiment, the visible light source 2012 emits light in the 430nm range that is transmitted by at least one optical fiber 2050 into anear canal. A plurality of optical fibers 2052, 2054 capture thereflected light and transmit the reflected light 2042 to the firstphotodetector circuit 2030 and the second photodetector circuit 2032.The first photodetector circuit 2030 and the second photodetectorcircuit 2032 detect the reflected light 2042 and determine a power orenergy level of the fluorescent emission in the 430 nm range in thereflected light 2042. The processor analyzes the fluorescent emission ofthe reflected light 2042 and correlates the fluorescent emission to aglucose concentration to obtain a glucose level measurement. A glucoselevel measurement can thus be obtained using photoacoustic spectrometry.

The analytic biosensor 2000 is thus configured to obtain glucose levelmeasurements using a plurality of measurement techniques, includinginfrared absorption spectroscopy, Raman spectroscopy, thermal emissionspectrometry, flourophoresence, and photoacoustic spectrometry. Theanalytic biosensor 2000 may then wirelessly transfer the glucose levelmeasurement to a gateway or glucose meter or user device. In anotherembodiment, the analytic biosensor 2000 may include a wired networkinterface card that is operable to communicate with a user device orgateway over a wired connection. The interface card may include a USB,mini-USB, micro-USB or other type of interface for communicating withthe user device or gateway.

In an embodiment, the analytic biosensor 2000 is configured to determinea percentage of blood that is loaded with oxygen using pulse oximetry.The percentage of hemoglobin, the protein in blood that carries oxygen,within the blood SpO2 (Saturation of peripheral oxygen) is measuredusing the “tympanic” membrane inside the ear canal.

For example, the visible light source 2012 emits light having a firstwavelength, e.g. of 660 nm (“red light”), and the IR light source 2022emits IR light having a second wavelength, e.g. of 940 nm. Absorption oflight at these wavelengths differs significantly between blood loadedwith oxygen and blood lacking oxygen. Oxygenated hemoglobin absorbs moreof the IR light and allows more of the red light to pass through.Deoxygenated hemoglobin allows more of the IR light to pass through andabsorbs more of the red light. The visible and IR light sources 2012,2022 sequence through a cycle of alternating off and on for the twofrequencies. Ambient light may also be measured such that the processormay cancel out the foreground noise of the ambient light interface fromthe measurement. The ratio of the two absorptions (oxygenated hemoglobinversus deoxygenated hemoglobin) is converted to the saturation level ofperipheral oxygen SpO2 by the processing circuit 2002 based on theBeer-Lambert law.

Bilirubin concentrations in the blood and other types of analytes forexample can be measured by similar techniques as described above. Forexample, sodium and potassium levels or concentrations may be measuredusing similar techniques as described above.

FIG. 21 illustrates a logical flow diagram of an exemplary method 2100for obtaining a glucose level measurement using a plurality ofmeasurement techniques. A glucose level measurement is obtained using afirst measurement technique, wherein the first measurement techniqueincludes at least one of: Near-Infrared Spectrometry, Ramanspectrometry, Thermal Emission Spectrometry, Fluorescence andPhotoacoustic Spectrometry 2102. Another glucose level measurement isobtained using another measurement technique, wherein the anothermeasurement technique includes a different one of: Near-InfraredSpectrometry, Raman Spectrometry, Thermal Emission Spectrometry,Fluorescence and Photoacoustic Spectrometry 2104. It is then determinedwhether additional measurement techniques are available or scheduled2106. If so, another glucose level measurement is obtained using anothertechnique, wherein the another measurement technique includes adifferent one of: Near-Infrared Spectrometry, Raman Spectrometry,Thermal Emission Spectrometry, Fluorescence and PhotoacousticSpectrometry 2104.

If no other measurement techniques are scheduled or available 2106, theglucose level measurements obtained from the plurality of measurementtechniques are compared 2108. When the glucose level measurements aredetermined to be within a predetermined threshold, e.g. within a 10%margin of error threshold 2110, a final glucose measurement is obtainedfrom the plurality of measurement techniques 2114. The final glucosemeasurement may be obtained by calculating an average or a mean of theglucose level measurements obtained from the plurality of measurementtechniques.

When the glucose level measurements are not within a predeterminedthreshold, e.g. within a 10% margin of error threshold 2110, one or moreof the glucose level measurements may be repeated 2112. Bilirubinconcentrations in the blood and other types of analytes for example canbe measured using a similar method.

FIG. 22 illustrates a logical flow diagram of an exemplary method 2200for using a combination of measurement techniques to enable autocalibration. A glucose level measurement is obtained using a firstmeasurement technique, wherein the first measurement technique includesat least one of: Near-Infrared Spectrometry, Raman spectrometry, ThermalEmission Spectrometry, Fluorescence and Photoacoustic Spectrometry 2202.Another glucose level measurement is obtained using another measurementtechnique, wherein the another measurement technique includes adifferent one of: Near-Infrared Spectrometry, Raman Spectrometry,Thermal Emission Spectrometry, Fluorescence and PhotoacousticSpectrometry 2204. It is then determined whether additional measurementtechniques are available or scheduled 2206. If so, another glucose levelmeasurement is obtained using another technique, wherein the anothermeasurement technique includes a different one of: Near-InfraredSpectrometry, Raman Spectrometry, Thermal Emission Spectrometry,Fluorescence and Photoacoustic Spectrometry 2204.

When no other measurement techniques are scheduled or available 2206,obtain an average or mean of the glucose level measurements obtainedfrom the plurality of measurement techniques 2208. The average or meanis then compared with the individual glucose level measurements fromeach of the plurality of measurement techniques 2210. For example, adifference between an individual glucose level measurement and theaverage or mean is determined. Then, a calibration is obtained for eachof the plurality of measurement techniques based on the comparison 2212.For example, a difference between an individual glucose levelmeasurement from a first one of the plurality of measurement techniquesand the average or mean is determined. When the average or mean has adifference of 2% from the individual glucose level from a first one ofthe plurality of measurement techniques, then a calibration of 2% isassigned to the first one of the plurality of measurement techniques.

This calibration process may be performed hourly, daily, or weekly asneeded. The use of a plurality of calibration techniques thus allows forauto-calibration of the analytic biosensor 2000. Bilirubinconcentrations in the blood and other types of analytes for example canbe measured using a similar method. For example, sodium and potassiumlevels or concentrations may be measured as well using a plurality ofmeasurement techniques.

FIG. 23 illustrates a schematic block diagram of an exemplary embodimentof a spectroscopy biosensor 2300. The spectroscopy biosensor 2300 isconfigured to detect blood analytes, including glucose, using IRabsorption spectroscopy. In this embodiment, the spectroscopy biosensor2300 is configured as an ear biosensor in the one or more form factorsdescribed herein. The spectroscopy biosensor 2300 includes a processingcircuit 2302 and a memory 2304. For example, the memory 2304 is anon-transitory processor readable memory that stores instructions whichwhen executed by the processing circuit 2302, causes the processingcircuit 2302 to perform one or more functions described herein. Thespectroscopy biosensor 2300 includes a wireless transceiver 2306 that isconfigured to communicate directly with a user device 1416 or with oneor more gateways 1100, similarly as described herein with respect to theglucose biosensor 100. For example, the wireless transceiver 2306 mayoperate in the 900 MHz range over a serial link using a proprietaryprotocol or may utilize a standard protocol in the 900 MHz range, suchas IEEE 802.11ah, Zigbee, IEEE 802.15-11 etc. In other embodiments, thewireless transceiver 2306 operates in one or more other wirelessfrequency bands or protocols, such as near field communication, shortrange radio frequency, RFID, infrared link, Bluetooth, or other shortrange wireless communication protocol.

The spectroscopy biosensor 2300 includes a light emitter and detectorcircuit 2310 having a plurality of light sources for emitting IR lightand visible light. For example, the spectroscopy biosensor 2300 includesa visible light source 2312 and an IR light source 2322. The visiblelight source 2312 is configured to emit light across a broad spectrum offrequencies and includes, e.g. a laser or tri-color LED, such as an(RGB) LED, wherein each color of the LED is controlled separately. In anembodiment, a driver circuit 2318 is configured to drive each lead orcolor of the RGB LED separately to generate a broad spectrum of colorsto perform various non-invasive measurement techniques, as describedfurther herein. A light collimator 2316, such as a prism, may be used toalign a direction of the light emitted from the RGB LED 2314. Thespectroscopy biosensor 2300 also includes an IR light source 2322 and anassociated driver circuit 2324. The spectroscopy biosensor 2300 is thusconfigured to emit frequencies of light in at least the visible and IRelectromagnetic spectrum.

The spectroscopy biosensor 2300 includes one or more optical fibers2350, 2356 for transmitting emitted light from the plurality of lightsources into an ear canal. A first optical fiber 2350 may be used totransmit visible light 2326 emitted from the visible light source 2312into the ear canal and a second optical fiber 2356 may be used totransmit IR light emitted from the IR light source 2322 into the earcanal. In another embodiment, a single optical fiber may transmit boththe visible light 2326 and the IR light 2320 into the ear canal.

The light emitter and detector circuit 2310 further includes one or morephotodetector circuits, e.g., a first photodetector circuit 2330 and asecond photodetector circuit 2332. The first photodetector circuit 2330and the second photodetector circuit 2332 include, for example, one ormore photodiodes, phototransistors or other components operable todetect IR and visible light. The first photodetector circuit 2330 andthe second photodetector circuit 2332 may also include a firstspectrometer 2334 and a second spectrometer 2336, respectively or mayshare a single spectrometer. The first photodetector circuit 2330 andthe second photodetector circuit 2332 may be separate components areincluded in a single component. The first spectrometer 2334 and thesecond spectrometer 2336 detect an intensity of light as a function ofwavelength or of frequency. The spectrometers 2334, 2336 are thus eachable to perform a spectrum analysis of the reflected light. The firstphotodetector circuit 2330 and the second photodetector circuit 2332 arecoupled to a first A/D circuit 2338 and a second A/D circuit 2340.Alternatively, a single A/D circuit may be coupled to both the first andsecond photodetector circuits 2330, 2332.

The light emitter and detector circuit 2310 is optically coupled to oneor more optical fibers 2352, 2354 for capturing reflected light 2342from the ear canal. In an embodiment, the optical fibers 2352, 2354includes at least a first optical fiber 2352 optically coupled to thefirst photodetector circuit 2330 and a second optical fiber 2354optically coupled to the second photodetector circuit 2332. In anotherembodiment, only one photodetector circuit is employed wherein a singleoptical fiber 2352 is employed for capturing reflected IR and visiblelight and coupled to the single photodetector circuit 2330 for detectingthe reflected IR and visible light. In another embodiment, an opticalfiber is not employed but an earbud with an aperture is used to capturereflected light. Other configurations and numbers of optical fibers orother component or methods may also be employed for capturing thereflected light.

The plurality of optical fibers 2350, 2352, 2354, 2356 may be encasedwithin an earpiece or ear bud or other casing that is configured to fitwithin an outer ear canal of a patient. In an embodiment, the one ormore optical fibers 2350, 2356 optically coupled to the plurality oflight sources 2312, 2322 are configured to rest within the middle of theoptical fibers 2352, 2354 coupled to the photodetector circuits, 2330,2332. However, other configurations and numbers of optical fibers mayalso be implemented.

In use, the spectroscopy biosensor 2300 performs infrared absorptionspectroscopy to detect blood analytes and in specific to detect glucose.In an embodiment, the IR light source 2322 emits an IR light that istransmitted by at least one optical fiber 2356 into the ear canal. Aplurality of optical fibers 2352, 2354 capture the reflected IR lightand transmit the reflected IR light 2342 to the first photodetectorcircuit 2330 and the second photodetector circuit 2332. The firstphotodetector circuit 2330 and the second photodetector circuit 2332detect the reflected IR light. The first and second spectrometers 2334,2336 each analyze the reflected IR light to determine a first frequencyor wavelength response and a second frequency or wavelength response ofthe resonance absorption peaks of the reflected IR light. The first andsecond frequency/wavelength responses may be summed, averaged orotherwise processed to obtain a final frequency/wavelength response ofthe resonance absorption peaks of the reflected IR light.

The visible light source 2312 then emits a visible light that istransmitted by at least one optical fiber 2350 into the ear canal. Theplurality of optical fibers 2352, 2354 capture the reflected visiblelight and transmit the reflected visible light 2342 to the firstphotodetector circuit 2330 and the second photodetector circuit 2332.The first photodetector circuit 2330 and the second photodetectorcircuit 2332 detect the reflected visible light. The first and secondspectrometers 2334, 2336 each analyze the reflected visible light todetermine a spectrum response such as, the resonance absorption peaks ofthe reflected visible light. The spectrum response includes spectrallines that illustrate an intensity or power or energy at a frequency orwavelength in a spectral region of the reflected light. The firstspectral response generated by the first spectrometer 2334 and thesecond spectral response generated by the second spectrometer 2336 maybe summed, averaged or otherwise processed to obtain a final spectralresponse of the resonance absorption peaks of the reflected visiblelight.

The ratio of the resonance absorption peaks from the visible and IRlight can be calculated based on the Beer-Lambert law to determine aglucose level. The spectral response of pure glucose is determined, sothe molar attenuation coefficient c can be determined. For example, theresonance absorption peaks for pure glucose in the mid infrared rangingfrom 2.5 μm to about 16 μm along with their magnitudes are about 75peaks in the above range with different peak absorption values.

Measurements of decadic attenuation coefficient μ₁₀ are made at the IFlight wavelength λ and at a second wavelength for the visible light inorder to correct for possible interferences. The concentration c maythen be determined from the Beer-Lambert Law as:

$c = {\frac{\mu_{10}(\lambda)}{ɛ(\lambda)}.}$

In an embodiment, the wavelength of the IR light is in the IR range fromapproximately 700 nanometers (frequency 430 THz) to approximately 1 mm(300 GHz). More specifically, the IR light may have a wavelength ofapproximately 940 nm. In an embodiment, the wavelength of the visiblelight is in the visible light range from approximately 390 nm to 700 nm(430-770 THz). More specifically, the visible light may be blue lighthaving a wavelength in the range of 420-495 nm. In specific, the visiblelight may have a wavelength of approximately 430 nm. It has beendetermined that the resonance absorption peaks is unique for glucose atthis wavelength of 430 nm. The spectroscopy biosensor 2300 thus obtainsa glucose level measurement using infrared absorption spectroscopy.

For example, it is possible to measure the difference in absorptionspectra of glucose and water at a first wavelength λ₁ and the absorptionof water at a second wavelength λ₂. According to the Beer-Lambert law,light intensity will decrease logarithmically with path length l (suchas through an artery of length l). Assuming then an initial intensityI_(in) of light is passed through a path length l, a concentration C_(g)of glucose may be determined using the following equations:

At the first wavelength λ1, I ₁ =I _(in1*)10^(−(α) ^(g1) ^(C) ^(gw)^(+α) ^(w1) ^(C) ^(w) ⁾*^(l)

At the second wavelength λ2, I ₂ =I _(in2*)10^(−(α) ^(g2) ^(C) ^(gw)^(+α) ^(w2) ^(C) ^(w) ⁾*^(l)

wherein:

I_(in1) is the intensity of the initial light at λ₁

I_(in2) is the intensity of the initial light at λ₂

α_(g1) is the absorption coefficient of glucose in water at λ₁

α_(g2) is the absorption coefficient of glucose in water at λ₂

α_(w1) is the absorption coefficient of water at λ₁

α_(w2) is the absorption coefficient of water at λ₂

C_(gw) is the concentration of glucose and water

C_(w) is the concentration of water

Then letting R equal:

$R = \frac{\log_{10}\left( \frac{I_{1}}{I\; {in}_{1}} \right)}{\log_{10}\left( \frac{I_{2}}{I\; {in}_{2}} \right)}$

The concentration of glucose Cg may then be equal to:

${Cg} = {\frac{Cgw}{{Cgw} + {Cw}} = \frac{{\alpha_{w\; 2}R} - \alpha_{w\; 1}}{{\left( {\alpha_{w\; 2} - \alpha_{{gw}\; 2}} \right)*R} - \left( {\alpha_{w\; 1} - \alpha_{{gw}\; 1}} \right)}}$

The IR spectroscopy biosensor 2300 may thus determine the concentrationof glucose Cg using spectroscopy at two different wavelengths, a firstwavelength in the IR range and a second wavelength in the visible lightrange. In an embodiment, the first wavelength is approximately 940 nmand the second wavelength is approximately 430 nm. It has beendetermined that the IR light at 940 nm is highly absorbed by water whilethe visible light at 430 nm is absorbed as much by glucose.

The IR spectroscopy biosensor 2300 may also function as a pulse oximeterusing similar principles under Beer-lambert law to determine pulse andoxygen levels. For example, the first wavelength is approximately 940 nmand the second wavelength is approximately 640 nm when determining pulseand oxygen levels. The IR spectroscopy biosensor 2300 may also detectother types of analytes, such as sodium and potassium, using IRabsorption spectroscopy.

FIG. 24A illustrates a logical flow diagram of an embodiment of a method2400 for glucose monitoring using absorption spectroscopy. An IR lightis transmitted into the ear canal 2402. The reflected IR light iscaptured by one or more optical fibers 2352, 2354, and transmitted toone or more of the first photodetector circuit 2330 and the secondphotodetector circuit 2332. The reflected IR light is detected and aspectral response is determined 2404. For example, when twophotodetectors are utilized, the first and second spectrometers 2334,2336 perform a spectrum analysis to determine a first spectral responseand a second spectral response. The first and second spectral responsesmay be summed, averaged or otherwise processed to obtain a finalfrequency/wavelength response of the reflected IR light.

A visible light is transmitted into the ear canal 2406. The reflectedvisible light is captured by one or more optical fibers 2352, 2354 andtransmitted to the first photodetector circuit 2330 and the secondphotodetector circuit 2332. The reflected visible light is detected anda spectral response is determined 2408. For example, when twophotodetectors are utilized, the first photodetector circuit 2330 andthe second photodetector circuit 2332 detect the reflected visiblelight. The first and second spectrometers 2334, 2336 each analyze thereflected visible light to determine a first spectral response and asecond spectral response of the reflected visible light. The first andsecond spectral responses may be summed, averaged or otherwise processedto obtain a final frequency response of the reflected visible light.

A glucose level measurement is then obtained using the Beer Lambert Law2410. For example, the ratio of the resonance absorption peaks from thespectral responses of the visible and IR light can be calculated basedon the Beer-Lambert law as described herein or using other methods. Inan embodiment, the first IR light has a wavelength of approximately 940nm and the second visible light has a wavelength of approximately 430nm. It has been determined that the IR light at 940 nm is highlyabsorbed by water while the visible light at 430 nm is absorbed less byglucose.

FIG. 24B illustrates a graph 2418 of absorbance change versus wavelengthfor glucose and water. The line 2420 illustrates the absorbance changeof water while line 2430 illustrates the absorbance change of glucose.As seen in the graph 2418, the absorbance change of water 2420 isgreater in the wavelength range between approximately 420 and 450 nm.More specifically, the absorbance change of water 2420 is greater atapproximately 430 nm than for glucose 2430. Thus, there are advantagesfor using a wavelength in the range between approximately 420 and 450nm, and more specifically at approximately 430 nm.

Since the IR absorption spectroscopy described herein uses twofrequencies in different electromagnetic spectrums, e.g. visible and IRlight, the glucose level measurements are self-calibrating. Thespectroscopy biosensor 2300 thus does not need calibration using anothermeasurement technique, such as the finger prick method. The absorptionspectroscopy described herein is thus an accurate, non-invasive bloodanalytic and glucose monitoring method and device that eliminates thepain of drawing blood as well as eliminates a source of potentialinfection.

Bilirubin concentrations in the blood and other types of analytes forexample may also be measured by the spectroscopy biosensor 2300 using asimilar method based on the Beer-Lambert Law. For example, sodium andpotassium levels or concentrations may be measured as well using atleast two of UV light, visible light or IR light.

FIG. 25 illustrates a schematic block diagram of an embodiment of a skinbiosensor 2500. The skin biosensor 2500 includes similar components tothe spectroscopy biosensor 2300 and performs absorption spectroscopy toobtain a glucose level measurement. However, instead of measuringglucose levels through the ear canal, the skin biosensor 2500 performsabsorption spectroscopy on an area of skin. The area of skin may belocated on a fingertip, forehead, behind the ear, arm or other areas ofskin. The skin biosensor 2500 may be placed onto the skin area or abovethe skin area.

The skin biosensor 2500 includes a plurality of apertures for emittinglight and collecting light, e.g. rather than the plurality of opticalfibers. A first aperture 2510 is positioned with respect to the thevisible light source 2312 such that visible light 2326 may be emittedonto the skin area. The first aperture 2510 may also be positioned withrespect to the IR light source 2322 such that the IR light 2320 may beemitted into the skin area. In another embodiment, two differentapertures may be used.

The skin biosensor 2500 further includes a second aperture 2520positioned to allow reflected light 2342 to be detected by a firstphotodetector circuit 2330. Optionally, a third aperture 2530 may beused and positioned to allow reflected light 2342 to be detected by asecond photodetector circuit 2332. When a second photodetector circuit2332 is employed, in an embodiment, the first aperture 2510 is locatedbetween the second aperture 2520 and the third aperture 2530.

The skin biosensor 2500 performs absorption spectroscopy to obtain aglucose level measurement similarly as described herein using visiblelight and IR light. The skin biosensor 2500 may also function as a pulseoximeter and/or detect other types of analytes, such as sodium andpotassium, using absorption spectroscopy or other measurement techniquesdescribed herein. The analytic biosensor 2000 may then wirelesslytransfer the glucose level measurement to a gateway 1100 or glucosemeter 1200 or user device 1416. In another embodiment, the skinbiosensor 2500 may include a wired network interface card that isoperable to communicate with a user device 1416 or gateway 1100 over awired connection. The interface card may include a USB, mini-USB,micro-USB or other type of interface for communicating with the userdevice or gateway.

FIG. 26 illustrates a schematic block diagram of an embodiment of a skinpatch 2600 including a skin biosensor 2500. The skin patch 2600 mayinclude an adhesive strip 2602 to adhere to a skin area. The area ofskin may be located on a fingertip, forehead, behind the ear, arm orother areas of skin. The skin biosensor 2500 includes at least oneemitted light aperture 2620 positioned to emit IR light and visiblelight from an IR light source 2322 and visible light source 2312respectively, as shown in FIG. 25. In another embodiment, the at leastone emitted light aperture 2620 is positioned to emit IR light from theIR light source 2322 while a second emitted light aperture 2622 ispositioned to emit visible light from the visible light source 2312.Other numbers and configurations of emitted light apertures 2620, 2622may be also employed. In an embodiment, the one or more emitted lightapertures 2620, 2622 are positioned between a first reflected lightaperture 2630 and a second reflected light aperture 2632. Thepositioning of the reflected light apertures provides advantages incapturing reflected light from different angles and/or parts of the skinarea. In another embodiment, a single reflected light aperture 2630 isused. The skin biosensor 2500 may also function as a pulse oximeterand/or detect other types of analytes using absorption spectroscopy orother measurement techniques.

FIG. 27 illustrates a schematic block diagram of an embodiment of afinger clip 2700 including the skin biosensor 2500. The finger clip 2700includes an upper housing 2704 pivoted with respect to a lower housing2706. The upper housing 2704 and lower housing 2706 are configured toinsert a finger 2702. The upper housing 2704 includes a tab 2708 thatattaches to the attachment mechanism 2710 of the lower housing 2706. Aspring 2712 provides a force to hold the upper and lower housings aroundthe finger 2702.

The skin biosensor 2500 detects a glucose level from an area of skin onthe finger 2702, preferably on the fingertip area, using absorptionspectroscopy. The skin biosensor 2500 may also function as a pulseoximeter and/or detect other types of analytes using absorptionspectroscopy or other measurement techniques described herein.

In another embodiment, the visible light source 2312 and IR light source2322 are located in the lower housing 2706 of the finger clip 2700 whilethe one or more photodetector circuits 2330, 2332 are located in theupper housing 2704 of the finger clip 2700. The visible light source2312 and IR light source 2322 emit light from the lower housing 2706that is transmitted through a fingertip and detected by the one or morephotodetector circuits 2330, 2332 in the upper housing 2704. In otherembodiments, the components are reversed, and the visible light source2312 and IR light source 2322 are located in the upper housing 2704 ofthe finger clip 2700 while the one or more photodetector circuits 2330,2332 are located in the lower housing 2706 of the finger clip 2700. Thevisible light source 2312 and IR light source 2322 emit light from theupper housing 2704 that is transmitted through a fingertip and detectedby the one or more photodetector circuits 2330, 2332 in the lowerhousing 2706.

FIG. 28 illustrates a logical flow diagram of an embodiment of anothermethod 2800 for glucose monitoring using absorption spectroscopy. An IRlight is transmitted onto an area of skin 2802. The reflected IR lightis captured by one or more apertures 2520, 2530 and transmitted to oneor more photodetectors, 2330, 2332. The reflected IR light is detectedand a spectral response is determined 2804. For example, when twophotodetector circuits 2330, 2332 are employed, the first and secondspectrometers 2334, 2336 perform a spectral analysis to determineintensity levels over spectra of the reflected IR light. The first andsecond spectral responses may be summed, averaged or otherwise processedto obtain a final spectral response of the reflected IR light.

A visible light is transmitted onto the same area of skin 2806. Thereflected visible light is captured by one or more apertures 2520, 2530,and transmitted to one or more photodetectors, 2330, 2332. The reflectedvisible light is detected and a spectral response is determined 2808.For example, when two photodetector circuits 2330, 2332 are employed,the first photodetector circuit 2330 and the second photodetectorcircuit 2332 detect the reflected visible light. The first and secondspectrometers 2334, 2336 each analyze the reflected visible light todetermine a first spectral response and a second spectral response ofthe reflected visible light. The first and second spectral responses maybe summed, averaged or otherwise processed to obtain a final spectralresponse of the reflected visible light.

A glucose level measurement is then obtained using the Beer Lambert Law2810 as described herein or using other methods. The measurements may berepeated for a predetermined interval. Thereafter, a rest period may beentered until the next measurements. Bilirubin concentrations in theblood and other types of analytes may also be measured using similarmethods based on the Beer-Lambert law as described herein. For example,sodium and potassium levels or concentrations may be measured as wellusing at least two of UV light, visible light or IR light.

Various embodiments of non-invasive glucose monitoring are describedherein. The The embodiments help to provide an accurate, non-invasiveblood analytic and glucose monitoring methods and devices. Theembodiments may be self-calibrating or need only occasional calibrationby other techniques. This eliminates the need for the finger prickmethod to check glucose levels thus reducing the pain of drawing bloodas well as eliminating a source of potential infection.

A processing circuit includes at least one processing device, such as amicroprocessor, micro-controller, digital signal processor,microcomputer, central processing unit, field programmable gate array,programmable logic device, state machine, logic circuitry, analogcircuitry, digital circuitry, and/or any device that manipulates signals(analog and/or digital) based on hard coding of the circuitry and/oroperational instructions. A memory is a non-transitory memory device andmay be an internal memory or an external memory, and the memory may be asingle memory device or a plurality of memory devices. The memory may bea read-only memory, random access memory, volatile memory, non-volatilememory, static memory, dynamic memory, flash memory, cache memory,and/or any non-transitory memory device that stores digital information.

As may be used herein, the term “operable to” or “configurable to”indicates that an element includes one or more of circuits,instructions, modules, data, input(s), output(s), etc., to perform oneor more of the described or necessary corresponding functions and mayfurther include inferred coupling to one or more other items to performthe described or necessary corresponding functions. As may also be usedherein, the term(s) “coupled”, “coupled to”, “connected to” and/or“connecting” or “interconnecting” includes direct connection or linkbetween nodes/devices and/or indirect connection between nodes/devicesvia an intervening item (e.g., an item includes, but is not limited to,a component, an element, a circuit, a module, a node, device, networkelement, etc.). As may further be used herein, inferred connections(i.e., where one element is connected to another element by inference)includes direct and indirect connection between two items in the samemanner as “connected to”.

As may be used herein, the terms “substantially” and “approximately”provides an industry-accepted tolerance for its corresponding termand/or relativity between items. Such an industry-accepted toleranceranges from less than one percent to fifty percent and corresponds to,but is not limited to, frequencies, wavelengths, component values,integrated circuit process variations, temperature variations, rise andfall times, and/or thermal noise. Such relativity between items rangesfrom a difference of a few percent to magnitude differences.

Note that the aspects of the present disclosure may be described hereinas a process that is depicted as a schematic, a flowchart, a flowdiagram, a structure diagram, or a block diagram. Although a flowchartmay describe the operations as a sequential process, many of theoperations can be performed in parallel or concurrently. In addition,the order of the operations may be re-arranged. A process is terminatedwhen its operations are completed. A process may correspond to a method,a function, a procedure, a subroutine, a subprogram, etc. When a processcorresponds to a function, its termination corresponds to a return ofthe function to the calling function or the main function.

The various features of the disclosure described herein can beimplemented in different systems and devices without departing from thedisclosure. It should be noted that the foregoing aspects of thedisclosure are merely examples and are not to be construed as limitingthe disclosure. The description of the aspects of the present disclosureis intended to be illustrative, and not to limit the scope of theclaims. As such, the present teachings can be readily applied to othertypes of apparatuses and many alternatives, modifications, andvariations will be apparent to those skilled in the art.

In the foregoing specification, certain representative aspects have beendescribed with reference to specific examples. Various modifications andchanges may be made, however, without departing from the scope as setforth in the claims. The specification and figures are illustrative,rather than restrictive, and modifications are intended to be includedwithin the scope of the claims. Accordingly, the scope should bedetermined by the claims and their legal equivalents rather than bymerely the examples described. For example, the components and/orelements recited in any apparatus claims may be assembled or otherwiseoperationally configured in a variety of permutations and areaccordingly not limited to the specific configuration recited in theclaims.

Furthermore, certain benefits, other advantages and solutions toproblems have been described above with regard to particularembodiments; however, any benefit, advantage, solution to a problem, orany element that may cause any particular benefit, advantage, orsolution to occur or to become more pronounced are not to be construedas critical, required, or essential features or components of any or allthe claims.

As used herein, the terms “comprise,” “comprises,” “comprising,”“having,” “including,” “includes” or any variation thereof, are intendedto reference a nonexclusive inclusion, such that a process, method,article, composition or apparatus that comprises a list of elements doesnot include only those elements recited, but may also include otherelements not expressly listed or inherent to such process, method,article, composition, or apparatus. Other combinations and/ormodifications of the above-described structures, arrangements,applications, proportions, elements, materials, or components used inthe practice of embodiments, in addition to those not specificallyrecited, may be varied or otherwise particularly adapted to specificenvironments, manufacturing specifications, design parameters, or otheroperating requirements without departing from the general principles ofthe same.

Moreover, reference to an element in the singular is not intended tomean “one and only one” unless specifically so stated, but rather “oneor more.” Unless specifically stated otherwise, the term “some” refersto one or more. All structural and functional equivalents to theelements of the various aspects described throughout this disclosurethat are known or later come to be known to those of ordinary skill inthe art are expressly incorporated herein by reference and are intendedto be encompassed by the claims. Moreover, nothing disclosed herein isintended to be dedicated to the public regardless of whether suchdisclosure is explicitly recited in the claims. No claim element isintended to be construed under the provisions of 35 U.S.C. § 112(f) as a“means-plus-function” type element, unless the element is expresslyrecited using the phrase “means for” or, in the case of a method claim,the element is recited using the phrase “step for.”

1. A biosensor, comprising: a light emitter and detector circuitconfigured to: emit light at a first wavelength and a second wavelengthonto tissue of a user; obtain a first spectral response of reflectedlight at the first wavelength and a second spectral response ofreflected light at the second wavelength; and a processing circuitconfigured to: obtain a first glucose level measurement using the firstspectral response and the second spectral response; obtain a secondglucose level measurement using another measurement technique, whereinthe another measurement technique includes at least one of:Near-Infrared Spectrometry, Raman Spectrometry, Thermal EmissionSpectrometry, flourophoresence, photoacoustic spectrometry, or anotherglucose measurement method; and determine a calibration for the firstglucose level measurement using the second glucose level measurement. 2.The biosensor of claim 1, wherein the first wavelength is in aninfra-red (IR) spectrum and the second wavelength of light is in avisible spectrum; and wherein the processing circuit is furtherconfigured to obtain the first glucose level measurement using a ratioof the first spectral response and the second spectral response.
 3. Thebiosensor of claim 2, wherein the ratio of the first spectral responseand the second spectral response are calculated based on Beer-Lambertlaw.
 4. The biosensor of claim 3, wherein the processing circuit isfurther configured to: obtain the second glucose level measurement fromuser input, wherein the second glucose level measurement includes ablood testing method.
 5. The biosensor of claim 4, wherein the biosensorfurther comprises: a wireless transceiver configured to communicate witha user device, wherein the wireless transceiver receives the secondglucose level measurement from the user device.
 6. The biosensor ofclaim 4, wherein the processing circuit is further configured to:determine a difference between the first glucose level measurement andthe second glucose level measurement; and adjust the first glucose levelmeasurement using the difference.
 7. The biosensor of claim 1, whereinthe processing circuit is further configured to analyze one or moreother spectral responses to determine the second glucose levelmeasurement, wherein the second glucose level measurement is obtainedusing at least one of: Near-Infrared Spectrometry, Raman Spectrometry,Thermal Emission Spectrometry, flourophoresence, or photoacousticspectrometry.
 8. The biosensor of claim 1, wherein the processingcircuit is further configured to: obtain the second glucose levelmeasurement from user input, wherein the second glucose levelmeasurement is obtained using at least one of: Near-InfraredSpectrometry, Raman Spectrometry, Thermal Emission Spectrometry,flourophoresence, or photoacoustic spectrometry.
 9. The biosensor ofclaim 8, wherein the processing circuit is further configured to:determine an average or mean of the first glucose level measurement andthe second glucose level measurement; determine a difference between thefirst glucose level measurement and the average or mean; and adjust thefirst glucose level measurement using the difference.
 10. A biosensor,comprising: a light emitter and detector circuit configured to: emitlight in an IR and visible spectrum onto tissue of a user; obtain afirst spectral response including reflected IR light and a secondspectral response including reflected visible light; and a processingcircuit configured to: obtain a first glucose level measurement using aratio determined from the first spectral response of the reflected IRlight and the second spectral response of the reflected visible light;obtain a second glucose level measurement using another measurementtechnique, wherein the another measurement technique includes at leastone of: Near-Infrared Spectrometry, Raman Spectrometry, Thermal EmissionSpectrometry, flourophoresence, or photoacoustic spectrometry; anddetermine a calibration for the first glucose level measurement usingthe second glucose level measurement.
 11. The biosensor of claim 10,wherein the light emitter and detector circuit is configured to detect afrequency shift in reflected light from a predetermined frequency rangeof emitted light; and wherein the processing circuit is furtherconfigured to obtain the second glucose level measurement using RamanSpectrometry.
 12. The biosensor of claim 10, wherein the processingcircuit is further configured to obtain the second glucose levelmeasurement by measuring an amount of infrared radiation naturallyemitted from tympanic membrane in an ear canal using Thermal EmissionSpectrometry.
 13. The biosensor of claim 10, wherein the light emitterand detector circuit is configured to: emit light in a 430 nm range ontotissue of the user; and determine a power or energy level of fluorescentemission in the 430 nm range; and wherein the processing circuit isfurther configured to correlate the power or energy level of fluorescentemission to obtain the second glucose level measurement.
 14. Thebiosensor of claim 10, wherein the light emitter and detector circuit isconfigured to obtain resonance absorption peaks in a near-IR spectrumreflected from tissue of the user; and wherein the processing circuit isfurther configured to compare the obtained resonance absorption peaks toexpected resonance absorption peaks for glucose to determine the secondglucose level measurement.
 15. The biosensor of claim 10, wherein theprocessing circuit is further configured to: determine an average ormean of the first glucose level measurement and the second glucose levelmeasurement; and determine a difference between the first glucose levelmeasurement and the average or mean; and adjust the first glucose levelmeasurement using the difference.
 16. A biosensor, comprising: a lightemitter and detector circuit configured to: emit light at a firstwavelength and a second wavelength onto tissue of a user; and obtain afirst spectral response of reflected light at the first wavelength and asecond spectral response of reflected light at the second wavelength;and a processing circuit configured to: obtain a first glucose levelmeasurement using the first spectral response and the second spectralresponse; obtain a second glucose level measurement using a blood test;and determine a calibration for the first glucose level measurementusing the second glucose level measurement.
 17. The biosensor of claim16, wherein the first wavelength is in an IR spectrum and the secondwavelength of light is in a visible spectrum; and wherein the processingcircuit is further configured to obtain the first glucose levelmeasurement using a ratio of the first spectral response and the secondspectral response.
 18. The biosensor of claim 17, wherein the ratio ofthe first spectral response and the second spectral response arecalculated based on Beer-Lambert law.
 19. The biosensor of claim 18,wherein the processing circuit is further configured to: obtain thesecond glucose level measurement from user input into a user device. 20.The biosensor of claim 19, wherein the biosensor further comprises: awireless transceiver configured to communicate with a user device,wherein the wireless transceiver receives the second glucose levelmeasurement from the user device.